Found 52 papers in cond-mat

Search terms: (topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99)

Emergence of Weyl Points due to Spin Orbit Coupling in LK-99
Bishnu Karki, Kai Chen, Pavan Hosur
arXiv:2402.18588v1 Announce Type: new Abstract: Recent reports of room temperature ambient pressure superconductivity in LK-99 sparked tremendous excitement. While the materials is no longer believed to be superconducting, interest in its electronic and topological properties still stands. Here, we utilize first-principle density functional theory and augment a recently proposed model tight-binding Hamiltonian to study the band topology including the impact of spin-orbit coupling. In the absence of spin-orbit coupling, we observed the presence of two isolated bands situated near the Fermi level. However, upon the introduction of spin-orbit coupling, these two bands split into four bands and generate multiple Weyl points with Chern number $\pm 2$. We also find accidental crossings along high symmetry lines which, at the level of our minimal Hamiltonian, extend as nodal surfaces away from these lines.

Topologically protected emergent Fermi surface in an Abrikosov vortex lattice
Songyang Pu, Jay D. Sau, Rui-Xing Zhang
arXiv:2402.18627v1 Announce Type: new Abstract: We show that a three-dimensional (3D) fully gapped type-II superconductor can feature emergent in-gap Fermi surfaces of Caroli-de Gennes Matricon (CdGM) quasiparticles in the presence of an Abrikosov vortex lattice. In particular, these CdGM Fermi surfaces manifest in the emergent 3D band structure enabled by the intervortex tunneling physics, and their stability is guaranteed by a $\mathbb{Z}_2$ topological index. By developing an effective analytical theory, we find that each vortex line carrying a 1D nodal dispersion is a sufficient condition for the vortex lattice to form CdGM Fermi surfaces. Following this prediction, in-gap CdGM Fermi surfaces are numerically confirmed in a microscopic vortex-lattice simulation of a superconducting Dirac semimetal with an $s$-wave spin-singlet pairing, which is directly applicable to a large class of type-II superconductors such as LiFeAs. Remarkably, the CdGM Fermi surfaces persist even when the normal state is deformed to a doped insulator of trivial band topology. Our work establishes the vortex lattice as a new experimentally feasible control knob for emergent topological phenomena in conventional superconductors.

Breakdown of the static dielectric screening approximation of Coulomb interactions in atomically thin semiconductors
Amine Ben Mhenni, Dinh Van Tuan, Leonard Geilen, Marko M. Petri\'c, Melike Erdi, Kenji Watanabe, Takashi Taniguchi, Sefaattin Tongay, Kai M\"uller, Nathan P. Wilson, Jonathan J. Finley, Hanan Dery, Matteo Barbone
arXiv:2402.18639v1 Announce Type: new Abstract: Coulomb interactions in atomically thin materials are uniquely sensitive to variations in the dielectric screening of the environment, which can be used to control quasiparticles and exotic quantum many-body phases. A static approximation of the dielectric response, where increased dielectric screening is predicted to cause an energy redshift of the exciton resonance, has been until now sufficient. Here, we use charge-tunable exciton resonances to study screening effects in transition metal dichalcogenide monolayers embedded in materials with dielectric constants ranging from 4 to more than 1000. In contrast to expectations, we observe a blueshift of the exciton resonance exceeding 30 meV for larger dielectric constant environments. By employing a dynamical screening model, we find that while the exciton binding energy remains mostly controlled by the static dielectric response, the exciton self-energy is dominated by the high-frequency response. Dielectrics with markedly different static and high-frequency screening enable the selective addressing of distinct many-body effects in layered materials and their heterostructures, expanding the tunability range and offering new routes to detect and control correlated quantum many-body states and to design optoelectronic and quantum devices.

Symmetry-breaking normal state response and surface superconductivity in topological semimetal YPtBi
Hyunsoo Kim, Tristin Metz, Halyna Hodovanets, Daniel Kraft, Kefeng Wang, Yun Suk Eo, Johnpierre Paglione
arXiv:2402.18735v1 Announce Type: new Abstract: Most of the half-Heusler RPtBi compounds (R=rare earth) host various surface states due to spin-orbit coupling driven topological band structure. While recent ARPES measurements ubiquitously reported the existence of surface states in RPtBi, their evidence by other experimental techniques remains elusive. Here we report the angle-dependent magnetic field response of electrical transport properties of YPtBi in both the normal and superconducting states. The angle dependence of both magnetoresistance and the superconducting upper critical field breaks the rotational symmetry of the cubic crystal structure, and the angle between the applied magnetic field and the measurement plane of a plate-like sample prevails. Furthermore, the measured upper critical field is notably higher than the bulk response for an in-plane magnetic field configuration, suggesting the presence of quasi-2D superconductivity. Our work suggests the transport properties cannot be explained solely by the bulk carrier response, requiring robust normal and superconducting surface states to flourish in YPtBi.

Discovery of magnetic phase transitions in heavy-fermion superconductor CeRh$_2$As$_2$
Grzegorz Chajewski, Dariusz Kaczorowski
arXiv:2402.18763v1 Announce Type: new Abstract: We report on the specific heat studies performed on a new generation of CeRh$_2$As$_2$ single crystals. Superior quality of the samples and dedicated experimental protocol allowed us to observe an antiferromagnetic-like behavior in the normal state and to detect the first-order phase transition of magnetic origin within the superconducting state of the compound. Although in the available literature the physical behavior of CeRh$_2$As$_2$ is most often described with the use of quadrupole density wave scenario, we propose an alternative explanation using analogies to antiferromagnetic heavy-fermion superconductors CeRhIn$_5$ and Ce$_2$RhIn$_8$.

Achieving quantized transport in Floquet topological insulators via energy filters
Ruoyu Zhang, Frederik Nathan, Netanel H. Lindner, Mark S. Rudner
arXiv:2402.18776v1 Announce Type: new Abstract: Due to photon-assisted transport processes, chiral edge modes induced by periodic driving do not directly mediate quantized transport. Here we show how narrow bandwidth "energy filters" can restore quantization by suppressing photon assisted transport through Floquet sidebands. We derive a Floquet Landauer type equation to describe transport through such an energy-filtered setup, and show how the filter can be integrated out to yield a sharply energy-dependent renormalized system-lead coupling. We show analytically and through numerical simulations that a nearly quantized conductance can be achieved in both off-resonantly and resonantly induced quasienergy gaps when filters are introduced. The conductance approaches the appropriate quantized value on each plateau with increasing system and filter size. We introduce a "Floquet distribution function" and show both analytically and numerically that it approaches the equilibrium Fermi-Dirac form when narrow-band filters are introduced, highlighting the mechanism that restores quantized transport.

Nanoscale variation of the Rashba energy in BiTeI
Ruizhe Kang, Jian-Feng Ge, Yang He, Zhihuai Zhu, Daniel T. Larson, Mohammed Saghir, Jason D. Hoffman, Geetha Balakrishnan, Jennifer E. Hoffman
arXiv:2402.18779v1 Announce Type: new Abstract: BiTeI is a polar semiconductor with strong spin-orbit coupling (SOC) that produces large Rashba spin splitting. Due to its potential utility in spintronics and magnetoelectrics, it is essential to understand how defects impact the spin transport in this material. Using scanning tunneling microscopy and spectroscopy, we image ring-like charging states of single-atom defects on the iodine surface of BiTeI. We observe nanoscale variations in the Rashba energy around each defect, which we correlate with the local electric field extracted from the bias dependence of each ring radius. Our data demonstrate the local impact of atomic defects on the Rashba effect, which is both a challenge and an opportunity for the development of future nanoscale spintronic devices.

Surface Luttinger surfaces and Luttinger-Lifshitz transitions in topological band structures
Kai Chen, Pavan Hosur
arXiv:2402.18820v1 Announce Type: new Abstract: The standard paradigm of topological phases posits that the surface two phases with the same symmetries are necessarily separated by a bulk phase transition, while breaking the symmetry unlocks a path in parameter space that allows the phases to be connected adiabatically. Moreover, if the symmetry is broken only on the boundary, single-particle properties are expected to be blind to distinction between the two phases. In this work, we prove that this expectation is incorrect. We first reveal that the single-particle \emph{surface} Green's function contains zeros or ``LSs'' that respect the same bulk-boundary correspondence that the well-known topological surface states do. At non-zero temperatures, these modes contribute negatively to an effective surface specific heat. Remarkably, the LSs survive symmetry-breaking perturbations that destroy the surface states. Thus, a bulk topological phase transition causes a reconstruction of Luttinger surfaces on the surface and manifests as a discontinuity in the surface specific heat.

Layer-dependent Raman spectroscopy of ultrathin Ta$_2$Pd$_3$Te$_5$
Zhenyu Sun, Zhaopeng Guo, Dayu Yan, Peng Cheng, Lan Chen, Youguo Shi, Yuan Huang, Zhijun Wang, Kehui Wu, Baojie Feng
arXiv:2402.18833v1 Announce Type: new Abstract: Two-dimensional topological insulators (2DTIs) or quantum spin Hall insulators are attracting increasing attention due to their potential applications in next-generation spintronic devices. Despite their promising prospects, realizable 2DTIs are still limited. Recently, Ta2Pd3Te5, a semiconducting van der Waals material, has shown spectroscopic evidence of quantum spin Hall states. However, achieving controlled preparation of few- to monolayer samples, a crucial step in realizing quantum spin Hall devices, has not yet been achieved. In this work, we fabricated few- to monolayer Ta$_2$Pd$_3$Te$_5$ and performed systematic thickness- and temperature-dependent Raman spectroscopy measurements. Our results demonstrate that Raman spectra can provide valuable information to determine the thickness of Ta2Pd3Te5 thin flakes. Moreover, our angle-resolved polarized Raman (ARPR) spectroscopy measurements show that the intensities of the Raman peaks are strongly anisotropic due to the quasi-one-dimensional atomic structure, providing a straightforward method to determine its crystalline orientation. Our findings may stimulate further efforts to realize quantum devices based on few or monolayer Ta$_2$Pd$_3$Te$_5$.

Exploring rare-earth Kitaev magnets by massive-scale computational analysis
Seong-Hoon Jang, Yukitoshi Motome
arXiv:2402.18837v1 Announce Type: new Abstract: The Kitaev honeycomb model plays a pivotal role in the quest for quantum spin liquids, in which fractional quasiparticles would provide applications in decoherence-free topological quantum computing. The key ingredient is the bond-dependent Ising-type interactions, dubbed the Kitaev interactions, which require strong entanglement between spin and orbital degrees of freedom. This study investigates the identification and design of rare-earth materials displaying robust Kitaev interactions. We scrutinize all possible $4f$ electron configurations, which require up to $6+$ million intermediate states in the perturbation processes, by developing a parallel computational program designed for massive scale calculations. Our analysis reveals a predominant interplay between the isotropic Heisenberg $J$ and anisotropic Kitaev $K$ interactions across all realizations of the Kramers doublets. Remarkably, instances featuring $4f^3$ and $4f^{11}$ configurations showcase the prevalence of $K$ over $J$, presenting unexpected prospects for exploring the Kitaev QSLs in compounds including Nd$^{3+}$ and Er$^{3+}$, respectively. Beyond the Kitaev model, our computational program also proves adaptable to a wide range of $4f$-electron magnets.

Exchange bias induced by spin-glass-like state in Te-rich FeGeTe van der Waals ferromagnet
Shaojie Hu, Xiaomin Cui, Zengji Yue, Pangpang Wang, Kohei Ohnishi, Shu-Qi Wu, Sheng-qun Su, Osamu Sato, Sunao Yamada, Takashi Kimura
arXiv:2402.18887v1 Announce Type: new Abstract: We have experimentally investigated the mechanism of the exchange bias in the 2D van der Waals (vdW) ferromagnets by means of the anomalous Hall effect (AHE) together with the dynamical magnetization property. The temperature dependence of the AC susceptibility with its frequency response indicates a glassy transition of the magnetic property for the Te-rich FeGeTe vdW ferromagnet. We also found that the irreversible temperature dependence in the anomalous Hall voltage follows the Almeida-Thouless line. Moreover, the freezing temperature of the spin-glass-like phase is found to correlate with the disappearance temperature of the exchange bias. These important signatures suggest that the emergence of magnetic exchange bias in the 2D van der Waals ferromagnets is induced by the presence of the spin-glass-like state in FeGeTe. The unprecedented insights gained from these findings shed light on the underlying principles governing exchange bias in vdW ferromagnets, contributing to the advancement of our understanding in this field.

Direct Visualization of Disorder Driven Electronic Liquid Crystal Phases in Dirac Nodal Line Semimetal GdSbTe
Balaji Venkatesan, Syu-You Guan, Jen-Te Chang, Shiang-Bin Chiu, Po-Yuan Yang, Chih-Chuan Su, Tay-Rong Chang, Kalaivanan Raju, Raman Sankar, Somboon Fongchaiya, Ming-Wen Chu, Chia-Seng Chang, Guoqing Chang, Hsin Lin, Adrian Del Maestro, Ying-Jer Kao, Tien-Ming Chuang
arXiv:2402.18893v1 Announce Type: new Abstract: Electronic liquid crystal (ELC) phases are spontaneous symmetry breaking states believed to arise from strong electron correlation in quantum materials such as cuprates and iron pnictides. Here, we report a direct observation of ELC phases in a Dirac nodal line (DNL) semimetal GdSbxTe2-x. As topological materials with symmetry protected Dirac or Weyl fermions are mostly weakly correlated, the discovery of real-space electronic nanostructures displaying incommensurate smectic charge modulation and intense local nematic order are anomalous and raise questions on the origin of emergent ELC phases. Specifically, we demonstrate how chemical substitution generates these symmetry breaking phases before the system undergoes a charge density wave - orthorhombic structural transition. We further show how dopants can induce nematicity via quasiparticle scattering interference. Our results highlight the importance of impurities in realizing ELC phases and present a new material platform for exploring the interplay among quenched disorder, topology and electron correlation.

Vibrational properties differ between halide and chalcogenide perovskite semiconductors, and it matters for optoelectronic performance
K. Ye, M. Menahem, T. Salzillo, B. Zhao, S. Niu, F. Knoop, I. Sadeghi, O. Hellman, J. Ravichandran, R. Jaramillo, O. Yaffe
arXiv:2402.18957v1 Announce Type: new Abstract: We report a comparative study of temperature-dependent photoluminescence and structural dynamics of two perovskite semiconductors, the chalcogenide BaZrS$_3$ (BZS) and the halide CsPbBr$_3$ (CPB). These materials have similar crystal structures and direct band gaps, but we find that they have quite distinct optoelectronic and vibrational properties. Both materials exhibit thermally-activated non-radiative recombination, but the non-radiative recombination rate in BZS is between two and four orders-of-magnitude faster than in CPB. Raman spectroscopy reveals that the effects of phonon anharmonicity are far more pronounced in CPB than in BZS. Further, although both materials feature a large dielectric response due to low-energy polar optical phonons, the phonons in CPB are substantially lower in energy than in BZS. Our results suggest that electron-phonon coupling in BZS is more effective at non-radiative recombination than in CPB, and that BZS may also have a substantially higher concentration of non-radiative recombination centers than CPB. The low defect concentration in CPB may be related to the ease of lattice reconfiguration, typified by anharmonic bonding. It remains to be seen to what extent these differences are inherent to the chalcogenide and halide perovskites and to what extent they can be affected by materials processing; comparing BZS single-crystals and thin films provides reason for optimism.

Domain growth kinetics of active model B with thermal fluctuations
Shambhavi Dikshit, Sudipta Pattanayak, Shradha Mishra, Sanjay Puri
arXiv:2402.18977v1 Announce Type: new Abstract: We perform a comprehensive study on the role of thermal noise on the ordering kinetics of a collection of active Brownian particles modeled using coarse-grained conserved active model B (AMB). The ordering kinetics of the system is studied for the critical mixture when quenched from high to a low temperature. The structure of the growing domains changes from isolated droplet type for AMB without noise to bi-continuous type for active model B with noise (AMBN). Unlike the passive counterpart of the AMB, the noise is relevant for the growth kinetics of the AMB. We use extensive numerical study, as well as dynamic scaling hypothesis to characterize the kinetics of the system. We find that the asymptotic growth law for AMBN is diffusive Lifshitz-Slyozov (LS) type, whereas it was reported previously that the asymptotic growth law for the AMB without noise is slower, with a growth exponent 4. Moreover, the kinetics of the growing domains show a strong time dependent growth for AMBN. The growth law shows a crossover from early time 1/3 value to intermediate time 1/4 value, and it again traverses from 1/4 to 1/3 asymptotically. The two different scaling functions are found for intermediate time and late time with growth law 1/4 and 1/3 respectively.

Blume-Capel model analysis with microcanonical population annealing method
Vyacheslav Mozolenko, Lev Shchur
arXiv:2402.18985v1 Announce Type: new Abstract: We present a modification of the Rose-Machta algorithm (Phys. Rev. E 100 (2019) 063304) and estimate the density of states for a two-dimensional Blume-Capel model, simulating $10^5$ replicas in parallel for each set of parameters. We perform a finite-size analysis of the specific heat and Binder cumulant, determine the critical temperature along the critical line, and evaluate the critical exponents. The results obtained are in good agreement with those obtained previously using various methods -- Markov Chain Monte Carlo simulation, Wang-Landau simulation, transfer matrix, and series expansion. The simulation results clearly illustrate the typical behavior of specific heat along the critical lines and through the tricritical point.

Triplet fermions in MXenes: The Applications for spintronic-based devices
Phusit Nualpijit, Bumned Soodchomshom
arXiv:2402.19039v1 Announce Type: new Abstract: We investigate the electronic properties of MXenes by three bands tight-binding model of \d_{z^2} , \d_{xy} , and \d_{x^2-y^2} orbitals. The three corresponding bands touch each other at high symmetry K point in the case of absence of spin-orbit interaction. The proper parameters can be obtained by Slater-Koster parameters related to chemical bonding, \pi, \sigma, and \delta bonds. The model calculated for these band structures make an agreement with the same trend as discussed in DFT calculation which the hopping parameters may be identified roughly by fermi velocity. Furthermore, the triplet fermion occurs around K point hosting by flat band, leading to super-Klein tunnelling and anti-super-Klein tunnelling for gapped and gapless pseudospin-1 fermion, respectively. These may apply for nanodevices operated by spin polarization which is more stable than that of the conventional two-dimensional materials.

Inertial spin waves in spin spirals
Mikhail Cherkasskii, Ritwik Mondal, Levente R\'ozsa
arXiv:2402.19141v1 Announce Type: new Abstract: Inertial effects in spin dynamics emerge on picosecond time scales, giving rise to nutational excitations at THz frequencies. Here, we describe a general framework for investigating the precessional and nutational excitations in any type of spin structure within linear spin-wave theory. We consider the particular cases of planar and conical spin spirals in detail. We observe a change in the sign of the curvature of the high-frequency nutational spin-wave band as the spiral period is decreased when passing from the ferromagnetic to the antiferromagnetic limit. We identify conditions for the interaction parameters where the curvature changes sign and asymptotical flat bands are formed.

Constrained hidden Markov models reveal further Hsp90 protein states
Riccardo Tancredi, Antonio Feltrin, Giosu\`e Sardo Infirri, Simone Toso, Leonie Vollmar, Thorsten Hugel, Marco Baiesi
arXiv:2402.19207v1 Announce Type: new Abstract: Time series of conformational dynamics in proteins are usually evaluated with hidden Markov models (HMMs). This approach works well if the number of states and their connectivity is known. But for the multi-domain protein Hsp90, a standard HMM analysis with optimization of the BIC (Bayesian information criterion) cannot explain long-lived states well. Therefore, here we employ constrained hidden Markov models, which neglect transitions between states by including assumptions. Gradually tuning a model with justified and focused changes allows us to improve its effectiveness and the score of the BIC. This became possible by analyzing time traces with several thousand observable transitions and, therefore, superb statistics. In this scheme, we also monitor the residences in the states reconstructed by the model, aiming to find exponentially distributed dwell times. We show how introducing new states can achieve these statistics but also point out limitations, e.g., for substantial similarity of two states connected to a common neighbor. One of the states displays the lowest free energy and is likely the idle open `waiting state', in which Hsp90 waits for the binding of nucleotides, cochaperones, or clients.

All epitaxial self-assembly of vertically-confined silicon color centers using ultra-low temperature epitaxy
Johannes Aberl, Enrique Prado Navarrete, Merve Karaman, Diego Haya Enriquez, Christoph Wilflingseder, Andreas Salomon, Daniel Primetzhofer, Markus Andreas Schubert, Giovanni Capellini, Thomas Fromherz, Peter De\'ak, \'Ad\'am Gali, Moritz Brehm
arXiv:2402.19227v1 Announce Type: new Abstract: Silicon-based color centers (SiCCs) have recently emerged as a source of quantum light that could be well combined with existing telecom-based Si Photonics platforms. However, considering the current SiCC fabrication processes, deterministic control over the vertical emitter position is impossible due to the stochastic nature of the ion implantation deployed for color center formation. To bypass this bottleneck towards high-yield integration, we demonstrate an entirely different creation method for various SiCCs, that relies solely on the epitaxial growth of Si and C-doped Si at untypically low temperatures in a pristine growth environment. Careful adjustment to the SiCC's thermal budget allows the emitters to be confined within a layer thickness of less than 1 nm embedded at an arbitrary vertical position within a highly crystalline Si matrix. Depending on the SiCC layer growth conditions and doping, different types of color centers, such as W centers, T centers, or G'-centers can be created, some of which are particularly promising as Si-based single photon sources and for spin-photon interfaces. We show that the zero-phonon emission from G'-center ensembles can be conveniently tuned by changing the C-doping concentration, characterized by a systematic wavelength shift and significant linewidth narrowing towards low emitter densities.

Electron conductance of a cavity-embedded topological 1D chain
Danh-Phuong Nguyen, Geva Arwas, Cristiano Ciuti
arXiv:2402.19244v1 Announce Type: new Abstract: We investigate many-body topological and transport properties of a one-dimensional Su-Schrieffer-Heeger (SSH) topological chain coupled to the quantum field of a cavity mode. The quantum conductance is determined via Green's function formalism in terms of light-matter eigenstates calculated via exact diagonalization for a finite number of electrons. We show that the topology of the cavity-embedded many-electron system is described by a generalized electron-photon Zak marker. We reveal how the quantization of transport is modified by the cavity vacuum fields for a finite-size chain and how it is impacted by electronic disorder. Moreover, we show that electron-photon entanglement produces dramatic differences with respect to the prediction of mean-field theory, which strongly underestimates cavity-modified effects.

Condensation Completion and Defects in 2+1D Topological Orders
Gen Yue, Longye Wang, Tian Lan
arXiv:2402.19253v1 Announce Type: new Abstract: We review the condensation completion of a modular tensor category, which yields a fusion 2-category of codimension-1 and higher defects in a $2+1$D topological order. We apply the condensation completion to $2+1$D toric code model and a $\mathbbm Z_4$ chiral topological order. In both cases, we explicitly enumerate the $1$d and $0$d defects present in these topological orders, along with their fusion rules. We also talk about other applications of condensation completion: alternative interpretations of condensation completion of a braided fusion category; condensation completion of the category of symmetry charges and its correspondence to gapped phases with symmetry; for a topological order $\cC$, one can also find all gapped boundaries of the stacking of $\cC$ with its time-reversal conjugate through computing the condensation completion of $\cC$.

Viscoelastic response and anisotropic hydrodynamics in Weyl semimetals
A. A. Herasymchuk, E. V. Gorbar, P. O. Sukhachov
arXiv:2402.19304v1 Announce Type: new Abstract: We study viscoelastic response in Weyl semimetals with broken time-reversal symmetry. Topology and anisotropy of the Fermi surface are manifested in the viscoelasticity tensor of the electron fluid. In the dynamic (inter-band) part of this tensor, the anisotropy leads to a qualitatively different, compared to isotropic models, scaling with frequency and the Fermi energy. While components of the viscosity tensor determined by the Fermi surface properties agree in the Kubo and kinetic formalisms, the latter misses the anomalous Hall viscosity determined by filled states below the Fermi surface. The anisotropy of the dispersion relation is also manifested in the acceleration and relaxation terms of the hydrodynamic equations.

Robust nodal behavior in the thermal conductivity of superconducting UTe$_2$
Ian M. Hayes, Tristin E. Metz, Corey E. Frank, Shanta R. Saha, Nicholas P. Butch, Vivek Mishra, Peter J. Hirschfeld, Johnpierre Paglione
arXiv:2402.19353v1 Announce Type: new Abstract: The superconducting state of the heavy-fermion metal UTe$_2$ has attracted considerable interest because of evidence for spin-triplet Cooper pairing and non-trivial topology. Progress on these questions requires identifying the presence or absence of nodes in the superconducting gap function and their dimension. In this article we report a comprehensive study of the influence of disorder on the thermal transport in the superconducting state of UTe$_2$. Through detailed measurements of the magnetic field dependence of the thermal conductivity in the zero-temperature limit, we obtain clear evidence for the presence of point nodes in the superconducting gap for all samples with transition temperatures ranging from 1.6~K to 2.1~K obtained by different synthesis methods, including a refined self-flux method. This robustness implies the presence of symmetry-imposed nodes throughout the range studied, further confirmed via disorder-dependent calculations of the thermal transport in a model with a single pair of nodes. In addition to capturing the temperature dependence of the thermal conductivity up to $T_c$, this model allows us to limit the possible locations of the nodes, suggesting a B$_{1u}$ or B$_{2u}$ symmetry for the superconducting order parameter. Additionally, comparing the new, ultra-high conductivity samples to older samples reveals a crossover between a low-field and a high field regime at a single value of the magnetic field in all samples. In the high field regime, the thermal conductivity at different disorder levels differ from each other by a simple offset, suggesting that some simple principle determines the physics of the mixed state, a fact which may illuminate trends observed in other clean nodal superconductors.

Signatures of Majorana protection in a three-site Kitaev chain
Alberto Bordin, Chun-Xiao Liu, Tom Dvir, Francesco Zatelli, Sebastiaan L. D. ten Haaf, David van Driel, Guanzhong Wang, Nick van Loo, Thomas van Caekenberghe, Jan Cornelis Wolff, Yining Zhang, Ghada Badawy, Sasa Gazibegovic, Erik P. A. M. Bakkers, Michael Wimmer, Leo P. Kouwenhoven, Grzegorz P. Mazur
arXiv:2402.19382v1 Announce Type: new Abstract: Majorana zero modes (MZMs) are non-Abelian excitations predicted to emerge at the edges of topological superconductors. One proposal for realizing a topological superconductor in one dimension involves a chain of spinless fermions, coupled through $p$-wave superconducting pairing and electron hopping. This concept is also known as the Kitaev chain. A minimal two-site Kitaev chain has recently been experimentally realized using quantum dots (QDs) coupled through a superconductor. In such a minimal chain, MZMs are quadratically protected against global perturbations of the QD electrochemical potentials. However, they are not protected from perturbations of the inter-QD couplings. In this work, we demonstrate that extending the chain to three sites offers greater protection than the two-site configuration. The enhanced protection is evidenced by the stability of the zero-energy modes, which is robust against variations in both the coupling amplitudes and the electrochemical potential variations in the constituent QDs. While our device offers all the desired control of the couplings it does not allow for superconducting phase control. Our experimental observations are in good agreement with numerical simulated conductances with phase averaging. Our work pioneers the development of longer Kitaev chains, a milestone towards topological protection in QD-based chains.

Magnon spectrum of altermagnets: Time-dependent matrix product states vs. linearized Holstein-Primakoff calculations unravelling spontaneous magnon decay
Federico Garcia-Gaitan, Ali Kefayati, John Q. Xiao, Branislav K. Nikolic
arXiv:2402.19433v1 Announce Type: new Abstract: The energy-momentum dispersion of magnons, viewed as noninteracting and infinitely long-lived quasiparticles describing collective low-energy excitations of magnetic materials, is often presented as sharp bands obtained from the effective quantum spin Hamiltonian, after being simplified via linearized Holstein-Primakoff (HP) transformations. However, magnons are prone to many-body interactions with other quasiparticles which can lead to their spontaneous decay. The magnon-magnon interactions could affect newly classified altermagnets. On the other hand, sharp bands of noninteracting chiral magnons in RuO2, as the canonical example of altermagnets, have been very recently predicted. Here, we employ nonperturbative numerically (quasi)exact quantum many-body calculations, via time-dependent matrix product states (TDMPS), to obtain magnon spectral function of RuO2. These calculations produce a broadened magnon dispersion, which overlaps with linearized HP theory sharp bands only at edges/center of the Brillouin zone. Substantially deviating otherwise. Artificially making exchange interaction within two sublattices of RuO2 closer in value forces these two spectra to overlap, thereby explaining the origin of the failure of linearized HP theory. Such features translate into the difference between their respective density of states, which we also compute and which could be tested by Raman scattering experiments. Finally, we employ popular Landau-Lifshitz-Gilbert (LLG) equation-based classical atomistic spin dynamics (ASD) simulations to obtain dynamical structure factor and extract magnon spectrum from it at finite temperature. Despite including magnon-magnon interactions via nonlinearity of LLG equation, ASD simulations cannot fully match the TDMPS-computed magnon spectrum due to nonclassical effects harbored by altermagnets.

First-principles electron-phonon interactions and electronic transport in large-angle twisted bilayer graphene
Shiyuan Gao, Jin-Jian Zhou, Yao Luo, Marco Bernardi
arXiv:2402.19453v1 Announce Type: new Abstract: Twisted bilayer graphene (tBLG) has emerged as an exciting platform for novel condensed matter physics. However, electron-phonon ($e$-ph) interactions in tBLG and their effects on electronic transport are not completely understood. Here we show first-principles calculations of $e$-ph interactions and resistivity in commensurate tBLG with large twist angles of 13.2 and 21.8 degrees. These calculations overcome key technical barriers, including large unit cells of up to 76 atoms, Brillouin-zone folding of the $e$-ph interactions, and unstable lattice vibrations due to the AA-stacked domains. We show that $e$-ph interactions due to layer-breathing (LB) phonons enhance intervalley scattering in large-angle tBLG. This interaction effectively couples the two layers, which are otherwise electronically decoupled at such large twist angles. As a result, the phonon-limited resistivity in tBLG deviates from the temperature-linear trend characteristic of monolayer graphene and tBLG near the magic angle. Taken together, our work quantifies $e$-ph interactions and scattering mechanisms in tBLG, revealing subtle interlayer coupling effects at large twist angles.

Topological flat bands, valley polarization, and interband superconductivity in magic-angle twisted bilayer graphene with proximitized spin-orbit couplings
Yang-Zhi Chou, Yuting Tan, Fengcheng Wu, Sankar Das Sarma
arXiv:2402.19478v1 Announce Type: new Abstract: We study theoretically the magic-angle twisted bilayer graphene with proximity-induced Ising and Rashba spin-orbit couplings on the top layer. We demonstrate topological flat bands and identify three distinct topological phases. Using a weak coupling analysis, we find that (partial) valley polarization prevails for a wide range of doping, suppressing the usual superconductivity with a pairing between time-reversal partners. Remarkably, we uncover that observable unconventional intervalley interband phonon-mediated superconductivity (with the highest $T_c\approx 1.2$K) can coexist with strong valley imbalance due to the approximate Fermi surface nesting between two flat bands not related by time-reversal symmetry, and the dominant pairing is an intersublattice Ising pairing, corresponding to a mixture of $p$- and $d$-waves. In contrast, the intrasublattice Ising phonon-mediated superconductivity with $s$- and $f$-wave mixing emerges in the absence of valley imbalance. Our work reveals a novel route of realizing unconventional superconductivity, and potentially explains the superconductivity phenomenology in existing experiments.

Single Electron Quantum Dot in Two-Dimensional Transition Metal Dichalcogenides
Jaros{\l}aw Paw{\l}owski, Pankaj Kumar, Kenji Watanabe, Takashi Taniguchi, Konstantin S. Novoselov, Hugh O. H. Churchill, Dharmraj Kotekar-Patil
arXiv:2402.19480v1 Announce Type: new Abstract: Spin-valley properties in two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDC) has attracted significant interest due to the possible applications in quantum computing. Spin-valley properties can be exploited in TMDC quantum dot (QD) with well-resolved energy levels. This requires smaller QDs, especially in material systems with heavy carrier effective mass e.g. TMDCs and silicon. Device architectures employed for TMDC QDs so far have difficulty achieving smaller QDs. Therefore, an alternative approach in the device architecture is needed. Here, we propose a multilayer device architecture to achieve a gate-defined QD in TMDC with a relatively large energy splitting on the QD. We provide a range of device dimensions and dielectric thicknesses and its correlation with the QD energy splitting. The device architecture is modeled realistically. Moreover, we show that all the device parameters used in modeling are experimentally achievable. These studies lay the foundation for future work toward spin-valley qubits in TMDCs. The successful implementation of these device architectures will drive the technological development of 2D materials-based quantum technologies.

Realizing Topological Quantum Walks on NISQ Digital Quantum Hardware
Mrinal Kanti Giri, Sudhindu Bikash Mandal, Bhanu Pratap Das
arXiv:2402.18685v1 Announce Type: cross Abstract: We study the quantum walk on the off-diagonal Aubry-Andre-Harper (AAH) lattice with quasiperiodic modulation using a digital quantum computer. Our investigation starts with exploring the single-particle quantum walk, where we study various initial states, hopping modulation strengths, and phase factors Initiating the quantum walk with a particle at the lattice edge highlights the robustness of the edge state due to the topological nature of the AAH model and reveals how this edge state is influenced by the phase factor. Conversely, when a particle starts the quantum walk from the lattice bulk, we observe the bulk walker being repelled from the edge, especially in the presence of strong hopping modulation. Furthermore, we investigate the quantum walk of two particles with nearest-neighbor interaction, emphasizing the repulsion between edge and bulk walkers caused by the interaction. Also, we explore the dynamics of two interacting particles in the lattice bulk and find interesting bulk localization through the formation of bound states influenced by the combined effect of hopping modulation and nearest-neighbor interaction. These features are analyzed by studying physical quantities like density evolution, quantum correlation, and participation entropy, and exploring their potential applications in quantum technologies.

Metasurface spectrometers beyond resolution-sensitivity constraints
Feng Tang, Jingjun Wu, Tom Albrow-Owen, Hanxiao Cui, Fujia Chen, Yaqi Shi, Lan Zou, Jun Chen, Xuhan Guo, Yijun Sun, Jikui Luo, Bingfeng Ju, Jing Huang, Shuangli Liu, Bo Li, Liming Yang, Eric Anthony Munro, Wanguo Zheng, Hannah J. Joyce, Hongsheng Chen, Lufeng Che, Shurong Dong, Tawfique Hasan, Xin Ye, Yihao Yang, Zongyin Yang
arXiv:2402.18996v1 Announce Type: cross Abstract: Optical spectroscopy plays an essential role across scientific research and industry for non-contact materials analysis1-3, increasingly through in-situ or portable platforms4-6. However, when considering low-light-level applications, conventional spectrometer designs necessitate a compromise between their resolution and sensitivity7,8, especially as device and detector dimensions are scaled down. Here, we report on a miniaturizable spectrometer platform where light throughput onto the detector is instead enhanced as the resolution is increased. This planar, CMOS-compatible platform is based around metasurface encoders designed to exhibit photonic bound states in the continuum9, where operational range can be altered or extended simply through adjusting geometric parameters. This system can enhance photon collection efficiency by up to two orders of magnitude versus conventional designs; we demonstrate this sensitivity advantage through ultra-low-intensity fluorescent and astrophotonic spectroscopy. This work represents a step forward for the practical utility of spectrometers, affording a route to integrated, chip-based devices that maintain high resolution and SNR without requiring prohibitively long integration times.

Mixing Times for the Facilitated Exclusion Process
James Ayre, Paul Chleboun
arXiv:2402.18999v1 Announce Type: cross Abstract: The facilitated simple exclusion process (FEP) is a one-dimensional exclusion process with a dynamical constraint. We establish bounds on the mixing time of the FEP on the segment, with closed boundaries, and the circle. The FEP on these spaces exhibits transient states that, if the macroscopic density of particles is at least $1/2$, the process will eventually exit to reach an ergodic component. If the macroscopic density is less than $1/2$ the process will hit an absorbing state. We show that the symmetric FEP (SFEP) on the segment $\{1,\ldots,N\}$, with $k>N/2$ particles, has mixing time of order $N^{2}\log(N-k)$ and exhibits the pre-cutoff phenomenon. For the asymmetric FEP (AFEP) on the segment, we show that there exists initial conditions for which the hitting time of the ergodic component is exponentially slow in the number of holes $N-k$. In particular, when $N-k$ is large enough, the hitting time of the ergodic component determines the mixing time. For the SFEP on the circle of size $N$, and macroscopic particle density $\rho \in(1/2,1)$, we establish bounds on the mixing time of order $N^{2}\log N$ for the process restricted to its ergodic component. We also give an upper bound on the hitting time of the ergodic component of order $N^{2}\log N$ for a large class of initial conditions. The proofs rely on couplings with exclusion processes (both open and closed boundaries) via a novel lattice path (height function) construction of the FEP.

Highly stable photoluminescence in vacuum-processed halide perovskite core-shell 1D nanostructures
Javier Castillo-Seoane, Lidia Contreras-Bernal, T. Cristina Rojas, Juan P. Espinos, Andres-Felipe Castro-Mendez, Juan-P. Correa-Baena, Angel Barranco, Juan R. Sanchez-Valencia, Ana Borras
arXiv:2402.19269v1 Announce Type: cross Abstract: Hybrid organometal halide perovskites (HP) present exceptional optoelectronic properties, but their poor long-term stability is a major bottleneck for their commercialization. Herein, we present a solvent-free approach to growing single-crystal organic nanowires (ONW), nanoporous metal oxide scaffolds, and HP to form a core@multishell architecture. The synthetic procedure is carried out under mild vacuum conditions employing thermal evaporation for the metal-free phthalocyanine (H2Pc) nanowires, which will be the core, plasma-enhanced chemical vapor deposition (PECVD) for the TiO2 shell, and co-evaporation of lead iodide (PbI2) and methylammonium iodide (CH3NH3I / MAI) for the CH3NH3PbI3 (MAPbI3 / MAPI) perovskite shell. We present a detailed characterization of the nanostructures by (S)-TEM and XRD, revealing a different crystallization of the hybrid perovskite depending on the template: while the growth on H2Pc nanowires induces the typical tetragonal structure of the MAPI perovskite, a low-dimensional phase (LDP) was observed on the one-dimensional TiO2 nanotubes. Such a combination yields an unprecedentedly stable photoluminescence emission over 20 hours and over 300 hours after encapsulation in polymethyl methacrylate (PMMA) under different atmospheres including N2, air, and high moisture levels. In addition, the unique one-dimensional morphology of the system, together with the high refractive index HP, allows for a strong waveguiding effect along the nanowire length.

Electron-correlated study of excited states and absorption spectra of some low-symmetry graphene quantum dots
Samayita Das, Alok Shukla
arXiv:2402.19320v1 Announce Type: cross Abstract: We have computed the linear optical absorption spectra of three graphene quantum dots (GQDs), saturated by hydrogens on the edges, using both first-principles time-dependent density-functional theory (TDDFT) and the Pariser-Parr-Pople (PPP) model coupled with the configuration-interaction (CI) approach. To understand the influence of electron-correlation effects, we have also calculated the singlet-triplet energy gap (spin gap) of the three GQDs. Because of the presence of edge hydrogens, these GQDs are effectively polycyclic aromatic hydrocarbons (PAHs) dibenzo[bc,ef]coronene (also known as benzo(1,14)bisanthene, C$_{30}$H$_{14}$), and two isomeric compounds, dinaphtho[8,1,2abc;2,1,8klm]coronene and dinaphtho[8,1,2abc;2,1,8jkl]coronene with the chemical formula C$_{36}$H$_{16}$. The two isomers have different point group symmetries, $C_{2v}$, and $C_{2h}$, therefore, this study will also help us understand the influence of symmetry on optical properties. A common feature of the absorption spectra of the three GQDs is that the first peak representing the optical gap is of low to moderate intensity, while the intense peaks appear at higher energies. For each GQD, PPP model calculations performed with the screened parameters agree well with the experimental results of the corresponding PAH, and also with the TDDFT calculations.

Single-electron states of phosphorus-atom arrays in silicon
Maicol A. Ochoa, Keyi Liu, Micha{\l} Zieli\'nski, Garnett W. Bryant
arXiv:2402.19392v1 Announce Type: cross Abstract: We characterize the single-electron energies and the wavefunction structure of arrays with two, three, and four phosphorus atoms in silicon by implementing atomistic tight-binding calculations and analyzing wavefunction overlaps to identify the single-dopant states that hybridize to make the array states. The energy spectrum and wavefunction overlap variation as a function of dopant separation for these arrays shows that hybridization mostly occurs between single-dopant states of the same type, with some cross-hybridization between $A_1$ and $E$ states occurring at short separations. We also observe energy crossings between hybrid states of different types as a function of impurity separation. We then extract tunneling rates for electrons in different dopants by mapping the state energies into hopping Hamiltonians in the site representation. Significantly, we find that diagonal and nearest neighbor tunneling rates are similar in magnitude in a square array. Our analysis also accounts for the shift of the on-site energy at each phosphorus atom resulting from the nuclear potential of the other dopants. This approach constitutes a solid protocol to map the electron energies and wavefunction structure into Fermi-Hubbard Hamiltonians needed to implement and validate analog quantum simulations in these devices.

Neutrino zeromodes on electroweak strings in light of topological insulators
Minoru Eto, Yu Hamada, Ryusuke Jinno, Muneto Nitta, Masatoshi Yamada
arXiv:2402.19417v1 Announce Type: cross Abstract: We examine neutrino zeromode solutions on the electroweak $Z$-string and their effect on the stability of the string in the standard model and its extensions. We propose using topological invariants constructed from the momentum (and real) space topology of Green's functions, often used for investigating edge modes in condensed matter physics. We analyze the standard model and then examine type-I and type-II extensions of the neutrino sector as well as their hybrid. Based on this analysis, we also comment on proposals in the literature to stabilize the $Z$-string.

Superconducting instability in non-Fermi liquids
Ipsita Mandal
arXiv:1608.01320v3 Announce Type: replace Abstract: We use renormalization group (RG) analysis and dimensional regularization techniques to study potential superconductivity-inducing four-fermion interactions in systems with critical Fermi surfaces of general dimensions ($m$) and co-dimensions ($d-m$), arising as a result of quasiparticle interaction with a gapless Ising-nematic order parameter. These are examples of non-Fermi liquid states in $d$ spatial dimensions. Our formalism allows us to treat the corresponding zero-temperature low-energy effective theory in a controlled approximation close to the upper critical dimension $d=d_c(m)$. The fixed points are identified from the RG flow equations, as functions of $d$ and $m$. We find that the flow towards the non-Fermi liquid fixed point is preempted by Cooper pair formation for both the physical cases of $(d=3, m=2)$ and $(d=2, m=1)$. In fact, there is a strong enhancement of superconductivity by the order parameter fluctuations at the quantum critical point.

Gilbert damping in metallic ferromagnets from Schwinger-Keldysh field theory: Intrinsically nonlocal and nonuniform, and made anisotropic by spin-orbit coupling
Felipe Reyes-Osorio, Branislav K. Nikolic
arXiv:2306.13013v4 Announce Type: replace Abstract: Understanding the origin of damping mechanisms in magnetization dynamics of metallic ferromagnets is a fundamental problem for nonequilibrium many-body physics of systems where quantum conduction electrons interact with localized spins assumed to be governed by the classical Landau-Lifshitz-Gilbert (LLG) equation. It is also of critical importance for applications, as damping affects energy consumption and speed of spintronic and magnonic devices. Since the 1970s, a variety of linear-response and scattering theory approaches have been developed to produce widely used formulas for computation of spatially-independent Gilbert scalar parameter as the magnitude of the Gilbert damping term in the LLG equation. The largely unexploited for this purpose Schwinger-Keldysh field theory (SKFT) offers additional possibilities, such as to rigorously derive an extended LLG equation by integrating quantum electrons out. Here we derive such equation whose Gilbert damping for metallic ferromagnets is nonlocal, i.e., dependent on all localized spins at a given time, and nonuniform, even if all localized spins are collinear and spin-orbit coupling (SOC) is absent. This is in sharp contrast to standard lore, where nonlocal damping is considered to emerge only if localized spins are noncollinear; for such situations, direct comparison on the example of magnetic domain wall shows that SKFT-derived nonlocal damping is an order of magnitude larger than the previously considered one. Switching on SOC makes such nonlocal damping anisotropic, in contrast to standard lore where SOC is usually necessary to obtain nonzero Gilbert damping scalar parameter. Our analytical formulas, with their nonlocality being more prominent in low spatial dimensions, are fully corroborated by numerically exact quantum-classical simulations.

c axis electrical transport at the metamagnetic transition in the heavy-fermion superconductor UTe2 under pressure
G. Knebel, A. Pourret, S. Rousseau, N. Marquardt, D. Braithwaite, F. Honda, D. Aoki, G. Lapertot, W. Knafo, G. Seyfarth, J-P. Brison, J. Flouquet
arXiv:2306.16273v2 Announce Type: replace Abstract: The electrical resistivity of the unconventional superconductor UTe$_2$ shows very anisotropic behavior in the normal state depending on the current direction. In the present paper we show that the maximum in the resistivity $\rho_c$ for current applied along the $c$ axis at $T^{\rm max}_{\rho_c} \approx 14.75$~K follows the minimum in the thermal expansion $T_\alpha^\star$ along $b$ axis. Under a magnetic field applied along the $b$ axis, $T^{\rm max}_{\rho_c}$ can be tracked up to the critical point of the first order metamagnetic transition, which is located near 6~K and 34.5~T. Surprisingly, at the metamagnetic field $H_m$ the resistivity $\rho_c$ shows a steplike decrease while the resistivities $\rho_a$ and $\rho_b$, for current along the $a$ and $b$ axis, respectively, show a steplike increase. Under hydrostatic pressure $T^{\rm max}_{\rho_c}$ and $H_m$ decrease significantly up to the critical pressure $p_c$ at which superconductivity is suppressed and a long range antiferromagnetic order appears. We show that the phase diagram at different pressures can be scaled by $T^{\rm max}_{\rho_c}$ in field and temperature suggesting that this temperature scale is governing the main interactions in the normal state.

Driving Mechanism and Dynamic Fluctuations of Charge Density Waves in the Kagome Metal ScV$_6$Sn$_6$
Shuyuan Liu, Chongze Wang, Shichang Yao, Yu Jia, Zhenyu Zhang, Jun-Hyung Cho
arXiv:2308.13796v2 Announce Type: replace Abstract: In a new family of V-based kagome metals RV$_6$Sn$_6$ (R = Sc, Y, La), only ScV$_6$Sn$_6$ was observed to exhibit the unusual charge density wave (CDW) with a $\sqrt{3}{\times}\sqrt{3}$ in-plane ordering and a tripling of the unit cell along the $c$-axis. However, the driving mechanism of such a $\sqrt{3}{\times}\sqrt{3}{\times}$3 CDW order is elusive. Here, using first-principles density-functional theory calculations, we demonstrate that the $\sqrt{3}{\times}\sqrt{3}{\times}$2 or $\sqrt{3}{\times}\sqrt{3}{\times}$3 CDW order is driven by a Jahn-Teller-like effect where the interlayer dimerization of Sn atoms in kagome bilayers is accompanied by a charge redistribution between such Sn atoms and its associated gap opening. It is revealed that the free energy of the $\sqrt{3}{\times}\sqrt{3}{\times}$3 phase becomes lower than that of the $\sqrt{3}{\times}\sqrt{3}{\times}$2 phase above $T_{\rm CDW}$ mostly due to the emergence of a large configurational entropy. Such a high-entropy phase shows dynamic fluctuations between its degenerate configurations but, as the temperature lowers below $T_{\rm CDW}$, it can be kinetically trapped to release a sizable entropy. Our findings not only identify the driving mechanism and order-disorder transition of the CDW in ScV$_6$Sn$_6$ but also provide an ideal platform for investigating strong CDW fluctuations in V-based kagome metals.

Theoretical analysis on the possibility of superconductivity in a trilayer Ruddlesden-Popper nickelate La$_4$Ni$_3$O$_{10}$ under pressure and its experimental examination: comparison with La$_3$Ni$_2$O$_7$
Hirofumi Sakakibara, Masayuki Ochi, Hibiki Nagata, Yuta Ueki, Hiroya Sakurai, Ryo Matsumoto, Kensei Terashima, Keisuke Hirose, Hiroto Ohta, Masaki Kato, Yoshihiko Takano, Kazuhiko Kuroki
arXiv:2309.09462v4 Announce Type: replace Abstract: We study the possibility of superconductivity in a trilayer Ruddlesden-Popper nickelate La$_4$Ni$_3$O$_{10}$ under pressure both theoretically and experimentally, making comparison with the recently discovered high $T_c$ superconductor La$_3$Ni$_2$O$_7$, a bilayer nickelate. Through DFT calculations, we find that a structural phase transition from monoclinic to tetragonal takes place around 10 - 15 GPa. Using the tetragonal crystal structure, we theoretically investigate the possibility of superconductivity, where a combination of fluctuation exchange approximation and linearized Eliashberg equation is applied to a six-orbital model constructed from first principles band calculation. The obtained results suggests that La$_4$Ni$_3$O$_{10}$ may also become superconducting under high pressure with $T_c$ comparable to some cuprates, although it is not as high as La$_3$Ni$_2$O$_7$. We also perform experimental studies using our polycrystalline samples of La$_3$Ni$_2$O$_{7.01}$ and La$_4$Ni$_3$O$_{9.99}$. The superconducting transition of La$_3$Ni$_2$O$_{7.01}$, with a maximum onset $T_c$ of 67.0 K at a pressure of 26.5 GPa, is confirmed by a drop in the electrical resistance, as well as the magnetic field dependence of the resistance. Quite interestingly, similar temperature and magnetic field dependencies of the resistance are observed also for La$_4$Ni$_3$O$_{9.99}$, where a drop in the resistance is observed at lower temperatures compared to La$_3$Ni$_2$O$_{7.01}$, under pressures of 32.8 GPa and above. Given the theoretical expectation, the reduction in the resistance can most likely be attributed to the occurrence of superconductivity in La$_4$Ni$_3$O$_{9.99}$. The temperature at which the resistance deviates from a linear behavior, considered as the onset $T_c$, monotonically increases up to 23 K at 79.2 GPa, which is opposite to the pressure dependence of $T_c$ in La3Ni2O7.01.

Layer-dependent transport properties in the Moir\'e of strained homobilayer transition metal dichalcogenides
Chao-Jie Ren, Zhao Gong, Hui-Ying Mu, Xing-Tao An, Wang Yao, Jian-Jun Liu
arXiv:2309.16268v2 Announce Type: replace Abstract: Bilayer moir\'e structures have attracted significant attention recently due to their spatially modulated layer degrees of freedom. However, the layer-dependent transport mechanism in the moir\'e structures is still a problem to be explored. Here we investigate the layer-dependent transport properties regulated by the strain, the interlayer bias and the number of moir\'e periods in a strained moir\'e homobilayer TMDs nanoribbon based on low-energy efficient models. The charge carriers can pass perfectly through the scattering region with the moir\'e potential. While, it is noted that the overall transmission coefficient is mainly contributed from either intralayer or interlayer transmissions. The transition of transport mechanism between intralayer and interlayer transmissions can be achieved by adjusting the strain. The intralayer transmissions are suppressed and one of the interlayer transmissions can be selected by a vertical external electric field, which can cause a controllable layer polarization. Moreover, the staggered intralayer and interlayer minigaps are formed as the number of moir\'e periods increases in the scattering region due to the overlap of the wave functions in two adjacent moir\'e periods. Our finding points to an opportunity to realize layer functionalities by the strain and electric field.

Fragility of the magnetic order in the prototypical altermagnet RuO$_2$
Andriy Smolyanyuk, Igor I. Mazin, Laura Garcia-Gassull, Roser Valent\'i
arXiv:2310.06909v2 Announce Type: replace Abstract: Altermagnetism is a topic that has lately been gaining attention and the RuO$_2$ compound is among one of the most studied altermagnetic candidates. However, the survey of available literature on RuO$_2$ properties suggests that there is no consensus about the magnetism of this material. By performing density functional theory calculations, we show that the electronic properties of stoichiometric RuO$_2$ are described in terms of a smaller Hubbard $U$ within DFT+$U$ than the value required to have magnetism. We further argue that Ru vacancies can actually aid the formation of a magnetic state in RuO$_2$. This in turn suggests that a characterization of the amount of Ru vacancies in experimental samples might help the resolution of the controversy between the different experimental results.

Quantifying magnetic field driven lattice distortions in kagome metals at the femto-scale using scanning tunneling microscopy
Christopher Candelora, Hong Li, Muxian Xu, Brenden R. Ortiz, Andrea Capa Salinas, Siyu Cheng, Alexander LaFleur, Ziqiang Wang, Stephen D. Wilson, Ilija Zeljkovic
arXiv:2310.12890v2 Announce Type: replace Abstract: A wide array of unusual phenomena has recently been uncovered in kagome solids. The charge density wave (CDW) state in the kagome superconductor AV3Sb5 in particular intrigued the community -- the CDW phase appears to break the time-reversal symmetry despite the absence of spin magnetism, which has been tied to exotic orbital loop currents possibly intertwined with magnetic field tunable crystal distortions. To test this connection, precise determination of the lattice response to applied magnetic field is crucial, but can be challenging at the atomic-scale. We establish a new scanning tunneling microscopy based method to study the evolution of the AV3Sb5 atomic structure as a function of magnetic field. The method substantially reduces the errors of typical STM measurements, which are at the order of 1% when measuring an in-plane lattice constant change. We find that the out-of-plane lattice constant of AV3Sb5 remains unchanged (within 10^-6) by the application of both in-plane and out-of-plane magnetic fields. We also reveal that the in-plane lattice response to magnetic field is at most at the order of 0.05%. Our experiments provide further constraints on time-reversal symmetry breaking in kagome metals, and establish a new tool for higher-resolution extraction of the field-lattice coupling at the nanoscale applicable to other quantum materials.

Ultrafast Electron Diffuse Scattering as a Tool for Studying Phonon Transport: Phonon Hydrodynamics and Second Sound Oscillations
Laurenz Kremeyer, Tristan L. Britt, Bradley J. Siwick, Samuel C. Huberman
arXiv:2310.18793v2 Announce Type: replace Abstract: Hydrodynamic phonon transport phenomena, like second sound, have been observed in liquid Helium more than 50 years ago. More recently second sound has been observed in graphite at over 200 K using transient thermal grating techniques. In this work we explore the signatures of second sound in ultrafast electron diffuse scattering (UEDS) patterns. We use density functional theory and solve the Boltzmann transport equation to determine time-resolved non-equilibrium phonon populations and subsequently calculate one-phonon structure factors and diffuse scattering patterns to simulate experimental data covering the regimes of ballistic, diffusive, and hydrodynamic phonon transport. For systems like graphite, UEDS is capable of extracting time-dependent phonon occupancies across the entire Brillouin zone and ultimately lead to a more fundamental understanding of the hydrodynamic phonon transport regime.

Chiral Symmetry Restoration and the Ultraquantum limit of Axionic Charge Density Waves in Weyl Semimetals
Joan Bernabeu, Alberto Cortijo
arXiv:2311.07644v3 Announce Type: replace Abstract: A new mechanism for chiral symmetry restoration at extreme high magnetic fields is proposed in the context of the Magnetic Catalysis scenario in Weyl Semimetals. Contrary to previous proposals, here we show that, at very large magnetic fields, the transverse velocity of the axion field, the phase mode of the chiral condensate $\langle \bar{\Psi}\Psi\rangle$, becomes effectively one-dimensional and its fluctuations destroy a possible nonzero value of this fermionic condensate. We also show that, despite of the $U(1)$ chiral symmetry not being broken at extremely large magnetic fields, the spectrum of the system is comprised by a well defined gapless bosonic excitation, connected to the axion mode, and a correlated insulating fermionic liquid that is neutral to $U(1)$ chiral transformations. When the theory is supplemented with the inclusion of dynamical electromagnetic fields, the chiral symmetry is broken again, and the conventional scenario of magnetic catalysis can be recovered.

Random walk models for the propagation of signalling molecules in one-dimensional spatial networks and their continuum limit
Adel Mehrpooya, Vivien J. Challis, Pascal R. Buenzli
arXiv:2312.03221v2 Announce Type: replace Abstract: The propagation of signalling molecules within cellular networks is affected by network topology, but also by the spatial arrangement of cells in the networks. Understanding the collective reaction--diffusion behaviour in space of signals propagating through cellular networks is an important consideration for example for regenerative signals that convey positional information. In this work, we consider stochastic and deterministic versions of random walk models of signalling molecules propagating and reacting within one-dimensional spatial networks with arbitrary node placement and connectivity. By taking a continuum limit of the random walk models, we derive an inhomogeneous reaction--diffusion--advection equation, where diffusivity and advective velocity depend on local node density and connectivity within the network. Our results show that large spatial variations of molecule concentrations can be induced by heterogeneous node distributions. Furthermore, we find that noise within the stochastic random walk model is directly influenced by node density. We apply our models to consider signal propagation within the osteocyte network of bone, where signals propagating to the bone surface regulate bone formation and resorption processes. We investigate signal-to-noise ratios for different damage detection scenarios and show that the location of perturbations to the network can be detected by signals received at the network boundaries.

Atomic-site dependent pairing gap in monolayer FeSe/SrTiO$_3$(001)- ($\sqrt{13} \times \sqrt{13}$)
Cui Ding, Zhongxu Wei, Wenfeng Dong, Hai Feng, Mingxia Shi, Lili Wang, Jin-Feng Jia, Qi-Kun Xue
arXiv:2312.10723v2 Announce Type: replace Abstract: The interfacial FeSe/TiO$_{2-\delta}$ coupling induces high-temperature superconductivity in monolayer FeSe films. Using cryogenic atomically resolved scanning tunneling microscopy/spectroscopy, we obtained atomic-site dependent surface density of states, work function, and pairing gap in the monolayer FeSe on SrTiO$_3$(001)-($\sqrt{13} \times \sqrt{13}$)-33.7${\deg}$ surface. Our results disclosed the out-of-plane Se-Fe-Se triple layer gradient variation, switched DOS for Fe sites on and off TiO$_{5\square}$, and inequivalent Fe sublattices, which gives global spatial modulation of pairing gap contaminant with the ($\sqrt{13} \times \sqrt{13}$) pattern. Moreover, the coherent lattice coupling induces strong inversion asymmetry and in-plane anisotropy in the monolayer FeSe, which is demonstrated to correlate with the particle-hole asymmetry in coherence peaks. The strong atomic-scale correlations in lattice and electronic structure, and pairing gap in particular, put constraints on exploring the unconventional high-temperature superconductivity emerging from interface coupling, e.g., strong demand for atomic-scale interface engineering and characterization.

Threshold displacement energy map of Frenkel pair generation in $\rm Ga_2O_3$ from machine-learning-driven molecular dynamics simulations
Huan He, Junlei Zhao, Jesper Byggm\"astar, Ru He, Kai Nordlund, Chaohui He, Flyura Djurabekova
arXiv:2401.14039v2 Announce Type: replace Abstract: $\beta$ phase gallium oxide ($\beta$-$\rm Ga_2O_3$) demonstrates tremendous potential for electronics applications and offers promising prospects for integration into future space systems with the necessity of high radiation resistance. Therefore, a comprehensive understanding of the threshold displacement energy (TDE) and the radiation-induced formation of Frenkel pairs (FPs) in this material is vital but has not yet been thoroughly studied. In this work, we performed over 5,000 molecular dynamics simulations using our machine-learning potentials to determine the TDE and investigate the formation of FPs. The average TDEs for the two Ga sites, Ga1 (tetrahedral site) and Ga2 (octahedral site), are 22.9 and 20.0 eV, respectively. While the average TDEs for the three O sites are nearly uniform, ranging from 17.0 to 17.4 eV. The generated TDE maps reveal significant differences in displacement behavior between these five atomic sites. Our developed defect identification methods successfully categorize various types of FPs in this material, with more than ten types of Ga FPs being produced during our simulations. O atoms are found to form two main types of FPs and the O split interstitial site on O1 site is most common. Finally, the recombination behavior and barriers of Ga and O FPs indicate that the O FP has a higher possibility of recovery upon annealing. Our findings provide important insights into the studies of radiation damage and defects in $\rm Ga_2O_3$ and can contribute to the design and development of $\rm Ga_2O_3$-based devices

Stabilizing topological superconductivity in disordered spin-orbit coupled semiconductor-superconductor heterostructures
Binayyak B. Roy, Rimika Jaiswal, Tudor D. Stanescu, Sumanta Tewari
arXiv:2402.18549v2 Announce Type: replace Abstract: We investigate theoretically a one-dimensional semiconductor-superconductor (SM-SC) heterostructure with Rashba spin-orbit coupling and parallel Zeeman field in the presence of disorder generated by random charged impurities and identify the optimal regimes for realizing topological superconductivity and Majorana zero modes. Using a Green's function approach, we show that upon increasing the disorder strength the stable topological superconducting phase characterized by robust end-to-end Majorana correlations "migrates" toward larger values of the Zeeman field and can be stabilized by increasing the effective SM-SC coupling. Based on these findings, we propose a strategy for accessing a regime characterized by well-separated Majorana zero modes that is based on (a) enhancing the strength of the effective SM-SC coupling (e.g., through interface engineering) and (b) expanding the range of accessible Zeeman fields (e.g., by enhancing the gyromagnetic ratio or optimizing the parent superconductor, to enable the application of larger magnetic fields). While this strategy may still require some reduction of the disorder strength, this requirement is significantly less strict than the corresponding requirement in a strategy that focuses exclusively on disorder reduction.

Crystallization of piezoceramic films on glass via flash lamp annealing
Longfei Song, Juliette Cardoletti, Alfredo Blazquez Martinez, Andreja Bencan, Brigita Kmet, Stephanie Girod, Emmanuel Defay, Sebastjan Glinsek
arXiv:2303.13103v3 Announce Type: replace-cross Abstract: Integration of thin-film oxide piezoelectrics on glass is imperative for the next generation of transparent electronics to attain sensing and actuating functions. However, their crystallization temperature (above 650 {\deg}C) is incompatible with most glasses. We developed a flash lamp process for growth of piezoelectric lead zirconate titanate films. The process enables crystallization on various types of glasses in a few seconds only. Functional properties of these films are comparable to the films processed with standard rapid thermal annealing at 700 {\deg}C. A surface haptic device was fabricated with a 1 $\unicode{x00B5}$m-thick film (piezoelectric e$_{33,f}$ of -5 C m$^{-2}$). Its ultrasonic surface deflection reached 1.5 $\unicode{x00B5}$m at 60 V, sufficient for its use in surface rendering applications. This flash lamp annealing process is compatible with large glass sheets and roll-to-roll processing and has the potential to significantly expand the applications of piezoelectric devices on glass.

Immersed figure-8 annuli and anyons
Bowen Shi
arXiv:2309.17155v2 Announce Type: replace-cross Abstract: Immersion (i.e., local embedding) is relevant to the physics of topologically ordered phases through entanglement bootstrap. An annulus can immerse in a disk or a sphere as a ``figure-8", which cannot be smoothly deformed to an embedded annulus. We investigate a simple problem: is there an Abelian state on the immersed figure-8 annulus, locally indistinguishable from the ground state of the background physical system? We show that if the answer is affirmative, a strong sense of isomorphism must hold: two homeomorphic immersed regions must have isomorphic information convex sets, even if they cannot smoothly deform to each other on the background physical system. We explain why to care about strong isomorphism in physical systems with anyons and give proof in the context of Abelian anyon theory. We further discuss a connection between immersed annuli and anyon transportation in the presence of topological defects. In appendices, we discuss related problems in broader contexts.

Generalised Hydrodynamics description of the Page curve-like dynamics of a freely expanding fermionic gas
Madhumita Saha, Manas Kulkarni, Abhishek Dhar
arXiv:2402.18422v2 Announce Type: replace-cross Abstract: We consider an analytically tractable model that exhibits the main features of the Page curve characterizing the evolution of entanglement entropy during evaporation of a black hole. Our model is a gas of non-interacting fermions on a lattice that is released from a box into the vacuum. More precisely, our Hamiltonian is a tight-binding model with a defect at the junction between the filled box and the vacuum. In addition to the entanglement entropy we consider several other observables, such as the spatial density profile and current, and show that the semiclassical approach of generalized hydrodynamics provides a remarkably accurate description of the quantum dynamics including that of the entanglement entropy at all times. Our hydrodynamic results agree closely with those obtained via exact microscopic numerics. We find that the growth of entanglement is linear and universal, i.e, independent of the details of the defect. The decay shows $1/t$ scaling for conformal defect while for non-conformal defects, it is slower. Our study shows the power of the semiclassical approach and could be relevant for discussions on the resolution of the black hole information paradox.

Found 4 papers in prb
Date of feed: Fri, 01 Mar 2024 04:16:58 GMT

Search terms: (topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99)

Orbital-selective correlations and renormalized electronic structure in LiFeAs
Huihang Lin, Rong Yu, Jian-Xin Zhu, and Qimiao Si
Author(s): Huihang Lin, Rong Yu, Jian-Xin Zhu, and Qimiao Si

Multiorbital physics is important to both the correlation physics and topological behavior of quantum materials. LiFeAs is a prototype iron pnictide suitable for in-depth investigation of this issue. Its electronic structure is strikingly different from the prediction of the noninteracting descripti…

[Phys. Rev. B 109, 075170] Published Thu Feb 29, 2024

Spin-orbit coupling tuned crossover of gapped and gapless topological phases in the chalcopyrite $\mathrm{HgSn}{X}_{2}$ ($X$ = N, P): An $ab initio$ investigation
Surasree Sadhukhan and Sudipta Kanungo
Author(s): Surasree Sadhukhan and Sudipta Kanungo

The coupling between electron orbital momentum and spin momentum, known as spin-orbit coupling (SOC), is a fundamental origin of a multitude of fascinating physical phenomena, especially it holds paramount significance in the realm of topological materials. In our paper, we have predicted the topolo…

[Phys. Rev. B 109, 075172] Published Thu Feb 29, 2024

Topological phases induced by charge fluctuations in Majorana wires
M. S. Shustin, S. V. Aksenov, and I. S. Burmistrov
Author(s): M. S. Shustin, S. V. Aksenov, and I. S. Burmistrov

The influence of many-body interactions on topological phases is one of the problems that still remains urgent in modern condensed-matter theory. In this study we address this issue within perturbative theory framework by considering topological phase transitions related to charge correlations in th…

[Phys. Rev. B 109, 075435] Published Thu Feb 29, 2024

Photoinduced high-Chern-number quantum anomalous Hall effect from higher-order topological insulators
Xiaolin Wan, Zhen Ning, Dong-Hui Xu, Rui Wang, and Baobing Zheng
Author(s): Xiaolin Wan, Zhen Ning, Dong-Hui Xu, Rui Wang, and Baobing Zheng

Quantum anomalous Hall (QAH) insulators with high Chern number host multiple dissipationless chiral edge channels, which are of fundamental interest and promising for applications in spintronics and quantum computing. Here, we propose a dynamic approach for achieving high-Chern-number QAH phases in …

[Phys. Rev. B 109, 085148] Published Thu Feb 29, 2024

Found 2 papers in prl
Date of feed: Fri, 01 Mar 2024 04:16:57 GMT

Search terms: (topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99)

Atomistic Origin of Diverse Charge Density Wave States in ${\mathrm{CsV}}_{3}{\mathrm{Sb}}_{5}$
Binhua Zhang, Hengxin Tan, Binghai Yan, Changsong Xu, and Hongjun Xiang
Author(s): Binhua Zhang, Hengxin Tan, Binghai Yan, Changsong Xu, and Hongjun Xiang

Kagome metals $A{\mathrm{V}}_{3}{\mathrm{Sb}}_{5}$ ($A=\mathrm{K}$, Rb, or Cs) exhibit intriguing charge density wave (CDW) instabilities, which interplay with superconductivity and band topology. However, despite firm observations, the atomistic origins of the CDW phases, as well as hidden instabil…

[Phys. Rev. Lett. 132, 096101] Published Thu Feb 29, 2024

Polar Self-Organization of Ferroelectric Nematic-Liquid-Crystal Molecules on Atomically Flat Au(111) Surface
Alexandr A. Marchenko, Oleksiy L. Kapitanchuk, Yaroslava Yu. Lopatina, Kostiantyn G. Nazarenko, Anton I. Senenko, Nathalie Katsonis, Vassili G. Nazarenko, and Oleg D. Lavrentovich
Author(s): Alexandr A. Marchenko, Oleksiy L. Kapitanchuk, Yaroslava Yu. Lopatina, Kostiantyn G. Nazarenko, Anton I. Senenko, Nathalie Katsonis, Vassili G. Nazarenko, and Oleg D. Lavrentovich

Using a scanning tunneling microscope polar molecular ordering in a monolayer of ferroelectric nematic liquid crystal has been directly observed for the first time.

[Phys. Rev. Lett. 132, 098101] Published Thu Feb 29, 2024

Found 8 papers in nano-lett
Date of feed: Thu, 29 Feb 2024 14:09:47 GMT

Search terms: (topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99)

[ASAP] Emergence of Improper Electronic Ferroelectricity and Flat Band in Twisted Bilayer Tl2S
Zhigang Gui, Wei Li, and Li Huang

TOC Graphic

Nano Letters
DOI: 10.1021/acs.nanolett.4c00141

[ASAP] Balancing the Ion/Electron Transport of Graphite Anodes by a La-Doped TiNb2O7 Functional Coating for Fast-Charging Li-Ion Batteries
Yeliang Sheng, Xinyang Yue, Wei Hao, Yongteng Dong, Yakun Liu, and Zheng Liang

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Nano Letters
DOI: 10.1021/acs.nanolett.3c05151

[ASAP] Resonant Tunneling-Enhanced Photoresponsivity in a Twisted Graphene van der Waals Heterostructure
Binghe Xie, Jiaxin Wu, Junning Mei, Shuangxing Zhu, Ruan Zhang, Feifan Gu, Kenji Watanabe, Takashi Taniguchi, and Xinghan Cai

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Nano Letters
DOI: 10.1021/acs.nanolett.3c05131

[ASAP] Quantification of Hybrid Topological Spin Textures and Their Nanoscale Fluctuations in Ferrimagnets
Yuxuan Zhang, Teng Xu, Wanjun Jiang, Rong Yu, and Zhen Chen

TOC Graphic

Nano Letters
DOI: 10.1021/acs.nanolett.3c04409

[ASAP] Direct Hot-Electron Transfer at the Au Nanoparticle/Monolayer Transition-Metal Dichalcogenide Interface Observed with Ultrahigh Spatiotemporal Resolution
Jinglin Tang, Yaolong Li, Sheng Ye, Pengzuo Jiang, Zhaohang Xue, Xiaofang Li, Xiaying Lyu, Qinyun Liu, Saisai Chu, Hong Yang, Chengyin Wu, Xiaoyong Hu, Yunan Gao, Shufeng Wang, Quan Sun, Guowei Lu, and Qihuang Gong

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Nano Letters
DOI: 10.1021/acs.nanolett.4c00324

[ASAP] Nonlinear Landau Fan Diagram for Graphene Electrons Exposed to a Moiré Potential
Pilkyung Moon, Youngwook Kim, Mikito Koshino, Takashi Taniguchi, Kenji Watanabe, and Jurgen H. Smet

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Nano Letters
DOI: 10.1021/acs.nanolett.3c04444

[ASAP] Ultralow Auger-Assisted Interlayer Exciton Annihilation in WS2/WSe2 Moiré Heterobilayers
Cheng-Syuan Cai, Wei-Yan Lai, Po-Hsuan Liu, Tzu-Chieh Chou, Ro-Ya Liu, Chih-Ming Lin, Shangjr Gwo, and Wei-Ting Hsu

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Nano Letters
DOI: 10.1021/acs.nanolett.3c04688

[ASAP] Topological Nodal-Point Superconductivity in Two-Dimensional Ferroelectric Hybrid Perovskites
Xiaoyin Li, Shunhong Zhang, Xiaoming Zhang, Zeev Valy Vardeny, and Feng Liu

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Nano Letters
DOI: 10.1021/acs.nanolett.3c04085

Found 3 papers in acs-nano
Date of feed: Thu, 29 Feb 2024 14:04:57 GMT

Search terms: (topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99)

[ASAP] Niobium Boride/Graphene Directing High-Performance Lithium–Sulfur Batteries Derived from Favorable Surface Passivation
Yanjuan Li, Zhanzhan Wang, HongFei Gu, Hongpeng Jia, Zhouyang Long, and Xiao Yan

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ACS Nano
DOI: 10.1021/acsnano.3c12076

[ASAP] Dual-Limit Growth of Large-Area Monolayer Transition Metal Dichalcogenides
Zeqin Xin, Xiaolong Zhang, Jing Guo, Yonghuang Wu, Bolun Wang, Run Shi, and Kai Liu

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ACS Nano
DOI: 10.1021/acsnano.3c09222

[ASAP] Atomistic Probing of Defect-Engineered 2H-MoTe2 Monolayers
Odongo Francis Ngome Okello, Dong-Hwan Yang, Seung-Young Seo, Jewook Park, Gunho Moon, Dongwon Shin, Yu-Seong Chu, Sejung Yang, Teruyasu Mizoguchi, Moon-Ho Jo, and Si-Young Choi

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ACS Nano
DOI: 10.1021/acsnano.3c08606

Found 2 papers in nat-comm

Search terms: (topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99)

Electron/infrared-phonon coupling in ABC trilayer graphene
< author missing >

Coherent control of enhanced second-harmonic generation in a plasmonic nanocircuit using a transition metal dichalcogenide monolayer
< author missing >