Found 36 papers in cond-mat

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Induced supersolidity and hypersonic flow of a dipolar Bose-Einstein Condensate in a rotating bubble trap
Hari Sadhan Ghosh, Soumyadeep Halder, Subrata Das, Sonjoy Majumder
arXiv:2402.13422v1 Announce Type: new Abstract: Motivated by the recent realization of space-borne Bose-Einstein Condensate (BEC) under micro-gravity conditions, we extend the understanding of ultracold dipolar bosonic gases by exploring their behavior in a novel trapping configuration known as the ``bubble trap" topology. Utilizing the three-dimensional numerical simulations within the extended Gross-Pitaevskii framework, we unveil diverse ground state phases in such a static curved topology. Subsequently, we investigate the influence of rotation on a dipolar BEC confined to the surface of a spherical bubble. Our findings reveal that the rotation of a bubble trap with certain rotation frequencies can modify the effective local dipole-dipole interaction strength, leading to the induction of supersolidity and the formation of quantum droplets. In addition, we demonstrate that a bubble trap can sustain high circulation and the flow also persists for a longer time. Significantly, adjusting the rf detuning parameter allows the condensate to achieve hypersonic velocity. Finally, we explore the impact of drastic change in the topological nature of the trap on the rotating dipolar BEC, transitioning from a filled shell trap to a bubble trap and vice versa.

Magnetotransport Signatures of the Radial Rashba Spin-Orbit Coupling in Proximitized Graphene
Wun-Hao Kang, Michael Barth, Aitor Garcia-Ruiz, Alina Mre\'nca-Kolasi\'nska, Ming-Hao Liu, Denis Kochan
arXiv:2402.13424v1 Announce Type: new Abstract: Graphene-based van der Waals heterostructures take advantage of tailoring spin-orbit coupling (SOC) in the graphene layer by proximity effect. At long-wavelength -- saddled by the electronic states near the Dirac points -- the proximitized features can be effectively modelled by the Hamiltonian involving novel SOC terms and allow for an admixture of the tangential and radial spin textures -- by the so-called Rashba angle $\theta_{\text{R}}$. Taking such effective models we perform realistic large-scale magneto-transport calculations -- transverse magnetic focusing and Dyakonov-Perel spin relaxation -- and show that there are unique qualitative and quantitative features allowing for an unbiased experimental disentanglement of the conventional Rashba SOC from its novel radial counterpart, called here the radial Rashba SOC. Along with that, we propose a scheme for a direct estimation of the Rashba angle by exploring the magneto-response symmetries when swapping an in-plane magnetic field. To complete the story, we analyze the magneto-transport signatures in the presence of an emergent Dresselhaus SOC and also provide some generic ramifications about possible scenarios of the radial superconducting diode effect.

Time- and angle-resolved photoemission spectroscopy with wavelength-tunable pump and extreme ultraviolet probe enabled by twin synchronized amplifiers
Takeshi Suzuki, Yigui Zhong, Kecheng Liu, Teruto Kanai, Jiro Itatani, Kozo Okazaki
arXiv:2402.13460v1 Announce Type: new Abstract: We describe a setup for time- and angle-resolved photoemission spectroscopy with wavelength-tunable excitation and extreme ultraviolet probe. It is enabled by using the 10 kHz twin Ti:sapphire amplifiers seeded by the common Ti:sapphire oscillator. The typical probe energy is 21.7 eV, and the wavelength of the pump excitation is tuned between 2400 and 1200 nm by using the optical parametric amplifier. The total energy resolution of 133 meV is achieved, and the time resolution is dependent on the wavelength for the pump, typically better than 100 fs. This system enables the pump energy to be matched with a specific interband transition and to probe a wider energy-momentum space. We present the results for the prototypical materials of highly oriented pyrolytic graphite and Bi2Se3 to show the performance of our system.

Thermal transport in a 2D amorphous material
Yuxi Wang, Xingxing Zhang, Wujuan Yan, Nianjie Liang, Haiyu He, Xinwei Tao, Ang Li, Fuwei Yang, Buxuan Li, Te-Huan Liu, Jia Zhu, Wu Zhou, Wei Wang, Lin Zhou, Bai Song
arXiv:2402.13471v1 Announce Type: new Abstract: Two-dimensional (2D) crystals proved revolutionary soon after graphene was discovered in 2004. However, 2D amorphous materials only became accessible in 2020 and remain largely unexplored. In particular, the thermophysical properties of amorphous materials are of great interest upon transition from 3D to 2D. Here, we probe thermal transport in 2D amorphous carbon. A cross-plane thermal conductivity ($\kappa$) down to 0.079 $\rm{Wm}^{-1}K^{-1}$ is measured for van der Waals stacked multilayers at room temperature, which is among the lowest reported to date. Meanwhile, an unexpectedly high in-plane $\kappa$ is obtained for freestanding monolayers which is a few times larger than what is predicted by conventional wisdom for 3D amorphous carbon with similar $\rm{sp}^{2}$ fraction. Our molecular dynamics simulations reveal the role of disorder and highlight the impact of dimensionality. Amorphous materials at the 2D limit open up new avenues for understanding and manipulating heat at the atomic scale.

Field-induced electric polarization and elastic softening caused by parity-mixed $d$-$p$ hybridized states with electric multipoles in Ba$_2$CuGe$_2$O$_7$
R. Kurihara, Y. Sato, A. Miyake, M. Akaki, K. Mitsumoto, M. Hagiwara, H. Kuwahara, M. Tokunaga
arXiv:2402.13504v1 Announce Type: new Abstract: We performed high-magnetic-field magnetization, polarization, and ultrasonic measurements in Ba$_2$CuGe$_2$O$_7$ to investigate field-induced multiferroic properties arising from a cross-correlation between electric dipoles and electric quadrupoles in addition to cross-correlation between magnetic dipoles and electric dipoles. Magnetization $M$ shows saturation behavior above 20 T for several magnetic field directions, however, electric polarization $P_c$ exhibits an increase, and elastic constants show a softening above 20 T. Based on quantum states with a crystalline electric field for the $D_{2d}$ point group and $d$-$p$ hybridization between Cu-$3d$ and O-$2p$ electrons, we confirmed that the matrix of an electric dipole $P_z$ was proportional to that of an electric quadrupole $O_{xy}$. Furthermore, considering the spin-orbit coupling of $3d$ electrons and the Zeeman effect, we showed that $P_z$ and $O_{xy}$ simultaneously exhibited field-induced responses. These findings indicate that the orbital degrees of freedom, in addition to the spin degrees of freedom, contribute to the high-field multiferroicity in Ba$_2$CuGe$_2$O$_7$.

Spin-selective transport in a correlated double quantum dot-Majorana wire system
Piotr Majek, Ireneusz Weymann
arXiv:2402.13515v1 Announce Type: new Abstract: In this work we investigate the spin-dependent transport through a double quantum dot embedded in a ferromagnetic tunnel junction and side attached to a topological superconducting nanowire hosting Majorana zero-energy modes. We focus on the transport regime when the Majorana mode leaks into the double quantum dot competing with the two-stage Kondo effect and the ferromagnetic-contact-induced exchange field. In particular, we determine the system's spectral properties and analyze the temperature dependence of the spin-resolved linear conductance by means of the numerical renormalization group method. Our study reveals unique signatures of the interplay between the spin-resolved tunneling, the Kondo effect and the Majorana modes, which are visible in the transport characteristics. In particular, we uncover a competing character of the coupling to topological superconductor and that to ferromagnetic leads, which can be observed already for very low spin polarization of the electrodes. This is signaled by an almost complete quenching of the conductance in one of the spin channels which is revealed through perfect conductance spin polarization. Moreover, we show that the conductance spin polarization can change sign depending on the magnitude of spin imbalance in the leads and strength of interaction with topological wire. Thus, our work demonstrates that even minuscule spin polarization of tunneling processes can have large impact on the transport properties of the system.

High-temperature stability of ambient-cured one-part alkali-activated materials incorporating graphene for thermal energy storage
Nghia Tran, Tuan Nguyen, Jay Black, Tuan Ngo
arXiv:2402.13543v1 Announce Type: new Abstract: In this research, the ambient cured one part alkali activated material (AAM) containing graphene nanoplatelets (GNPs), fly ash, slag and silica fume has been investigated after high temperature exposure to 200 to 800oC. Their compressive strength, thermal properties, microstructure, pore structure were characterised through visual observation, isothermal calorimetry, TGA, XRD, SEM-EDS and X-ray CT. The research findings indicated high strength characteristics of the developed AAM (80 MPa) at ambient condition, which could further reach to approx. 100 MPa after being heated up to 400oC. GNPs provided nucleation effects for promoting geopolymerisation and crystallisation. As observed from X-ray CT, a high extent of severe cracks initiated from the core and propagated towards the surface. From SEM-EDS analysis, high Na-Al and Na-Si ratios or low Si-Al and Ca-Si ratios highly correlated to thermal stability. Overall, the research outcomes implied the promising use of the nano-engineered AAMs for thermal energy storage (TES) at 400 to 600oC.

Fabrication of high electron mobility and high photoluminescence quantum yield nanoscrolled monolayer MoS2
C. Abinash Bhuyan, Kishore K. Madapu, K. Prabakar, K. Ganesan, A. Pandian, Sandip Dhara
arXiv:2402.13564v1 Announce Type: new Abstract: We fabricated the 1D nanoscrolled monolayer MoS2 (1L-MoS2) with superior characteristics from 1L-MoS2 film in a facile route, using a suitable organic solvent with optimum surface tension, evaporation rate and dielectric constant, which facilitates the controlled scroll formation. These nanoscrolls behave as multilayers in morphology and monolayer electronically. The nanoscrolls exhibited a direct optical gap with enhanced photoluminescence quantum yield stemming from the weak interlayer coupling among constituent layers and were corroborated by low-frequency Raman measurements and Kelvin probe force microscopy measurements. Furthermore, enhanced photoluminescence emission after annealing uncovers the thermal stability of nanoscrolls. In addition, conducting atomic force microscopy results exhibit a significantly higher photocurrent in the nanoscrolled 1L-MoS2 compared to the 1L-MoS2. We also realized significantly improved field effect transistor device parameters in nanoscrolled 1L-MoS2 devices. In nanoscrolled devices, we report the highest mobility value of 2400 cm2V-1s-1 reported in any form of 1L-MoS2.

Tunable topological phases in nanographene-based spin-1/2 alternating-exchange Heisenberg chains
Chenxiao Zhao, Gon\c{c}alo Catarina, Jin-Jiang Zhang, Jo\~ao C. G. Henriques, Lin Yang, Ji Ma, Xinliang Feng, Oliver Gr\"oning, Pascal Ruffieux, Joaqu\'in Fern\'andez-Rossier, Roman Fasel
arXiv:2402.13590v1 Announce Type: new Abstract: Unlocking the potential of topological order within many-body spin systems has long been a central pursuit in the realm of quantum materials. Despite extensive efforts, the quest for a versatile platform enabling site-selective spin manipulation, essential for tuning and probing diverse topological phases, has persisted. Here, we utilize on-surface synthesis to construct spin-1/2 alternating-exchange Heisenberg (AH) chains[1] with antiferromagnetic couplings $J_1$ and $J_2$ by covalently linking Clar's goblets -- nanographenes each hosting two antiferromagnetically-coupled unpaired electrons[2]. Utilizing scanning tunneling microscopy, we exert atomic-scale control over the spin chain lengths, parities and exchange-coupling terminations, and probe their magnetic response by means of inelastic tunneling spectroscopy. Our investigation confirms the gapped nature of bulk excitations in the chains, known as triplons[3]. Besides, the triplon dispersion relation is successfully extracted from the spatial variation of tunneling spectral amplitudes. Furthermore, depending on the parity and termination of chains, we observe varying numbers of in-gap $S=1/2$ edge spins, enabling the determination of the degeneracy of distinct topological ground states in the thermodynamic limit-either 1, 2, or 4. By monitoring interactions between these edge spins, we identify the exponential decay of spin correlations. Our experimental findings, corroborated by theoretical calculations, present a phase-controlled many-body platform, opening promising avenues toward the development of spin-based quantum devices.

Multi-step topological transitions among meron and skyrmion crystals in a centrosymmetric magnet
H. Yoshimochi, R. Takagi, J. Ju, N. D. Khanh, H. Saito, H. Sagayama, H. Nakao, S. Itoh, Y. Tokura, T. Arima, S. Hayami, T. Nakajima, S. Seki
arXiv:2402.13751v1 Announce Type: new Abstract: Topological swirling spin textures, such as skyrmions and merons, have recently attracted much attention as a unique building block for high-density magnetic information devices. The controlled transformation among different types of such quasi-particles is an important challenge, while it was previously achieved only in a few non-centrosymmetric systems characterized by Dzyaloshinskii-Moriya interaction. Here, we report an experimental discovery of multi-step topological transitions among a variety of meron and skyrmion crystal states in a centrosymmetric magnet GdRu$_2$Ge$_2$. By performing the detailed magnetic structure analysis based on resonant X-ray and neutron scattering experiments as well as electron transport measurements, we have found that this compound hosts periodic lattice of elliptic skyrmions, meron/anti-meron pairs, and circular skyrmions as a function of external magnetic field. The diameter of these objects is as small as 2.7 nm, which is almost two orders of magnitude smaller than typical non-centrosymmetric magnets. Such an intricate manner of topological magnetic transitions are well reproduced by a theoretical model considering the competition between RKKY interactions at inequivalent wave vectors. The present findings demonstrate that even a simple centrosymmetric magnet with competing interactions can be a promising material platform to realize a richer variety of nanometric magnetic quasi-particles with distinctive symmetry and topology, whose stability may be tunable by various external stimuli.

Critical Behavior and Collective Modes at the Superfluid Transition in Amorphous Systems
Vishnu Pulloor Kuttanikkad, Martin Puschmann, Rajesh Narayanan, Thomas Vojta
arXiv:2402.13757v1 Announce Type: new Abstract: We investigate the critical behavior and the dynamics of the amplitude (Higgs) mode close to the superfluid-insulator quantum phase transition in an amorphous system (i.e., a system subject to topological randomness). In particular, we map the two-dimensional Bose-Hubbard Hamiltonian defined on a random Voronoi-Delaunay lattice onto a (2+1)-dimensional layered classical XY model with correlated topological disorder. We study the resulting model by laying recourse to classical Monte Carlo simulations. We specifically focus on the scalar susceptibility of the order parameter to study the dynamics of the amplitude mode. To do so, we harness the maximum entropy method to perform the analytic continuation of the scalar susceptibility to real frequencies. Our analysis shows that the amplitude mode remains delocalized in the presence of such topological disorder, quite at odds with its behavior in generic disordered systems, where the randomness localizes the Higgs mode. Furthermore, we show that the critical behavior of the topologically disordered system is identical to that of its translationally invariant counterpart, consistent with a modified Harris criterion. This suggests that the localization of the collective excitations in the presence of disorder is tied to the critical behavior of the quantum phase transition rather than a simple Anderson-localization-type interference mechanism.

Coupled exciton internal and center-of-mass motions in two-dimensional semiconductors by a periodic electrostatic potential
Fujia Lu, Hongyi Yu
arXiv:2402.13759v1 Announce Type: new Abstract: We theoretically investigated the coupling between the exciton internal and center-of-mass motions in monolayer transition metal dichalcogenides subjected to a periodic electrostatic potential. The coupling leads to the emergence of multiple absorption peaks in the exciton spectrum which are the hybridizations of 1s, 2s and 2p$\pm$ Rydberg states with different center-of-mass momentums. The energies and wave functions of hybrid states can be strongly modulated by varying the profile of the periodic electrostatic potential, which well reproduces the recent experimental observations. Combined with the electron-hole exchange interaction, non-degenerate valley-coherent bright excitons can be realized by applying an in-plane electric field, with the valley coherence determined by the field direction.

Repulsive Casimir force from a Majorana zero-mode
C. W. J. Beenakker
arXiv:2402.13862v1 Announce Type: new Abstract: Fu and Kane have taught us that a Majorana zero-mode appears on the quantum spin Hall edge at the interface with a superconductor. If a magnetic scatterer is placed on the edge, the zero-point energy of massless edge excitations exerts a force on the scatterer. This is the fermionic analogue of the electromagnetic Casimir effect. We show that the Majorana zero-mode produces a repulsive Casimir force, pushing the scatterer away from the superconductor. Unlike some other signatures of Majorana zero-modes, the repulsive Casimir force is directly tied to the topological invariant of the system (the sign of the determinant of the reflection matrix from the superconductor).

Flux-periodic supercurrent oscillations in an Aharonov-Bohm-type nanowire Josephson junction
Patrick Zellekens, Russell S. Deacon, Farah Basaric, Raghavendra Juluri, Michael D. Randle, Benjamin Bennemann, Christoph Krause, Erik Zimmermann, Ana M. Sanchez, Detlev Gr\"utzmacher, Alexander Pawlis, Koji Ishibashi, Thomas Sch\"apers
arXiv:2402.13880v1 Announce Type: new Abstract: Phase winding effects in hollow semiconductor nanowires with superconducting shells have been proposed as a route to engineer topological superconducting states. We investigate GaAs/InAs core/shell nanowires with half-shells of epitaxial aluminium as a potential platform for such devices, where the thin InAs shell confines the electron wave function around the GaAs core. With normal contacts we observed pronounced $h/e$ flux periodic oscillations in the magnetoconductance, indicating the presence of a tubular conductive channel in the InAs shell. Conversely, the switching current in Josephson junctions oscillates with approximately half that period, i.e. $h/2e$, indicating transport via Andreev transport processes in the junction enclosing threading magnetic flux. On these structures, we systematically studied the gate-, field-, and temperature-dependent evolution of the supercurrent. Results indicate that Andreev transport processes can occur about the wire circumference indicating full proximitization of the InAs shell from the half-shell superconducting contacts.

Multigap superconductivity in lithium intercalated bilayer Mo$_2$C
Can Hong, Danhong Wu, Xi-Bo Li, Feipeng Zheng
arXiv:2402.13886v1 Announce Type: new Abstract: Interlayer coupling can significantly influence the physical properties of layered transition metal compounds. The superconductivity in layered Mo$_2$C systems, belonging to the emergent family of MXene, has garnered considerable attention. However, the impact of interlayer coupling on superconductivity, and the anisotropic superconducting properties in these systems are not yet clear. By performing first-principles calculations of electron-phonon coupling and anisotropic superconducting properties, we show that the interlayer coupling in bilayer 1$T$-Mo$_2$C suppresses superconductivity, resulting in a significant drop in superconducting transition temperature ($T_{\mathrm{c}}$) from 4.2 $K$ in its monolayer form to nearly 0 $K$. By introducing lithium atoms into the interlayer space of the bilayer, the interlayer coupling can be effectively weakened, transforming the system into a two-gap superconductor with a $T_{\mathrm{c}}$ above 10 $K$. A 3\% tensile strain can further transform the system into a three-gap superconductor with a significantly enhanced $T_{\mathrm{c}}$ of approximately 24.7 $K$, which is very high in the Mo$_2$C related systems. The enhancement of the superconductivity induced by the strain is mainly due to the downshift of an energy band with a flat dispersion to the energy near the Fermi level. The in-plane vibrations of Mo atoms and the $d$-orbital electrons of Mo atoms are most important for the formation of the superconductivity. Our method can also be applied to multilayer Mo$_2$C systems. Given the successful synthesis of layered Mo$_2$C systems and the experimental realization of alkaline metal atom depositions, our work presents a practically feasible strategy for achieving high $T_{\mathrm{c}}$ and multigap superconductivity in layered Mo$_2$C.

Quantum spin Hall effect protected by spin U(1) quasi-symmetry
Lu Liu, Yuntian Liu, Jiayu Li, Hua Wu, Qihang Liu
arXiv:2402.13974v1 Announce Type: new Abstract: Quantum spin Hall (QSH) effect, where electrons with opposite spin channels are deflected to opposite sides of a two-dimensional system with a quantized conductance, was believed to be characterized by a nontrivial topological index $Z_{2}$. However, spin mixing effects in realistic materials often lead to deviation of the spin Hall conductance from exact quantization. In this Letter, we present a universal symmetry indicator for diagnosing QSH effect in realistic materials, termed spin $U$(1) quasi-symmetry. Such a symmetry eliminates the first-order spin-mixing perturbation and thus protects the near-quantization of SHC, applicable to time-reversal-preserved cases with either $Z_{2}=1$ or $Z_{2}=0$, as well as time-reversal-broken scenarios. We propose that spin $U$(1) quasi-symmetry is hidden in the subspace spanned by the doublets with unquenched orbital momentum and emerges when SOC is present, which can be realized in 19 crystallographic point groups. Particularly, we identify a previous overlooked even spin Chern phase with a trivial $Z_{2}$ index as an ideal platform for achieving a near-double-quantized SHC, as exemplified by twisted bilayer transition metal dichalcogenides and monolayer RuBr$_{3}$. Our work offers a new perspective for understanding QSH effect and significantly expands the material pool for the screening of exemplary material candidates.

A General Theory of Static Response for Markov Jump Processes
Timur Aslyamov, Massimiliano Esposito
arXiv:2402.13990v1 Announce Type: new Abstract: We consider Markov jump processes on a graph described by a rate matrix that depends on various control parameters. We derive explicit expressions for the static responses of edge currents and steady-state probabilities. We show that they are constrained by the graph topology (i.e. the incidence matrix) by deriving response relations (i.e. linear constraints linking the different responses) and topology-dependent bounds. For unicyclic networks, all scaled current sensitivities are between zero and one and must sum to one. Applying these results to stochastic thermodynamics, we derive explicit expressions for the static response of fundamental currents (which carry the full dissipation) to fundamental thermodynamic forces (which drive the system away from equilibrium).

Interplay between 2D ferromagnetism and transport at the surface of FeSi
Keenan E. Avers, Yun Suk Eo, Hyeok Yoon, Jarryd A. Horn, Shanta R. Saha, Alonso Suarez, Peter Zavalij, Johnpierre Paglione
arXiv:2402.14006v1 Announce Type: new Abstract: FeSi is a curious example of a $d$-electron system that manifests many of the same phenomena associated with $f$-electron Kondo insulators, including conducting surface states with potentially non-trivial topology. Here we investigate the magnetization and magnetotransport of these surface states and how a 2D ferromagnetic state at the surface of FeSi influences the surface conductivity. We confirm the 2D ferromagnetism via a systematic study of magnetization on groups of filtered fragments with increasing surface area-to-volume ratios, identifying characteristic temperatures and magnetic fields associated with the ordered state. The paramagnetic to ferromagnetic transition appears broadened, suggesting disorder, which allows spin fluctuations to manifest up to at least 9 T at 2 K. This highlights the need to understand the relation between the disorder of the 2D ferromagnetism and the surface conductivity in FeSi.

Bipartite mutual information in classical many-body dynamics
Andrea Pizzi, Norman Y. Yao
arXiv:2402.13312v1 Announce Type: cross Abstract: Information theoretic measures have helped to sharpen our understanding of many-body quantum states. As perhaps the most well-known example, the entanglement entropy (or more generally, the bipartite mutual information) has become a powerful tool for characterizing the dynamical growth of quantum correlations. By contrast, although computable, the bipartite mutual information (MI) is almost never explored in classical many particle systems; this owes in part to the fact that computing the MI requires keeping track of the evolution of the full probability distribution, a feat which is rarely done (or thought to be needed) in classical many-body simulations. Here, we utilize the MI to analyze the spreading of information in 1D elementary cellular automata (CA). Broadly speaking, we find that the behavior of the MI in these dynamical systems exhibits a few different types of scaling that roughly correspond to known CA universality classes. Of particular note is that we observe a set of automata for which the MI converges parametrically slowly to its thermodynamic value. We develop a microscopic understanding of this behavior by analyzing a two-species model of annihilating particles moving in opposite directions. Our work suggests the possibility that information theoretic tools such as the MI might enable a more fine-grained characterization of classical many-body states and dynamics.

Combining unsupervised and supervised learning in microscopy enables defect analysis of a full 4H-SiC wafer
Binh Duong Nguyen, Johannes Steiner, Peter Wellmann, Stefan Sandfeld
arXiv:2402.13353v1 Announce Type: cross Abstract: Detecting and analyzing various defect types in semiconductor materials is an important prerequisite for understanding the underlying mechanisms as well as tailoring the production processes. Analysis of microscopy images that reveal defects typically requires image analysis tasks such as segmentation and object detection. With the permanently increasing amount of data that is produced by experiments, handling these tasks manually becomes more and more impossible. In this work, we combine various image analysis and data mining techniques for creating a robust and accurate, automated image analysis pipeline. This allows for extracting the type and position of all defects in a microscopy image of a KOH-etched 4H-SiC wafer that was stitched together from approximately 40,000 individual images.

Engineering Hierarchical Symmetries
Zhanpeng Fu, Roderich Moessner, Hongzheng Zhao, Marin Bukov
arXiv:2402.13519v1 Announce Type: cross Abstract: We present a general driving protocol for many-body systems to generate a sequence of prethermal regimes, each exhibiting a lower symmetry than the preceding one. We provide an explicit construction of effective Hamiltonians exhibiting these symmetries. This imprints emergent quasi-conservation laws hierarchically, enabling us to engineer the respective symmetries and concomitant orders in nonequilibrium matter. We provide explicit examples, including spatiotemporal and topological phenomena, as well as a spin chain realizing the symmetry ladder $\text{SU(2)}{\rightarrow}\text{U(1)} {\rightarrow} \mathbb{Z}_2{\rightarrow} E$.

Infrared Imaging using thermally stable HgTe/CdS nanocrystals
Huichen Zhang, Yoann Prado, Rodolphe Alchaar, Henri Lehouelleur, Mariarosa Cavallo, Tung Huu Dang, Adrien Khalili, Erwan Bossavit, Corentin Dabard, Nicolas Ledos, Mathieu G Silly, Ali Madouri, Daniele Fournier, James K. Utterback, Debora Pierucci, Victor Parahyba, Pierre Potet, David Darson, Sandrine Ithurria, Bart{\l}omiej Szafran, Benjamin T. Diroll, Juan I. Climente, Emmanuel Lhuillier
arXiv:2402.13745v1 Announce Type: cross Abstract: Transferring the nanocrystals (NCs) from the laboratory environment toward practical applications has raised new challenges. In the case of NCs for display and lightning, the focus was on reduced Auger recombination and maintaining luminescence at high temperatures. When it comes to infrared sensing, narrow band gap materials are required and HgTe appears as the most spectrally tunable platform. Its low-temperature synthesis reduces the growth energy cost yet also favors sintering. As a result, once coupled to a read-out circuit, the Joule effect aggregates the particles leading to a poorly defined optical edge and dramatically large dark current. Here, we demonstrate that CdS shells bring the expected thermal stability (no redshift upon annealing, reduced tendency to form amalgams and preservation of photoconduction after an atomic layer deposition process). The peculiar electronic structure of these confined particles is unveiled using k.p self-consistent simulations showing a significant exciton biding energy at around 200 meV. After shelling, the material displays a p-type behavior that favors the generation of photoconductive gain. The latter is then used to increase the external quantum

Topological Optical Waveguiding of Exciton-Polariton Condensates
Johannes Beierlein, Oleg A. Egorov, Philipp Gagel, Tristan H. Harder, Adriana Wolf, Monika Emmerling, Simon Betzold, Fauzia Jabeen, Libo Ma, Sven H\"ofling, Ulf Peschel, Sebastian Klembt
arXiv:2402.13943v1 Announce Type: cross Abstract: One-dimensional models with topological non-trivial band structures are a simple and effective way to study novel and exciting concepts in topological photonics. In this work we are studying the propagation of light-matter quasi-particles, so called exciton-polaritons, in waveguide arrays. Specifically, we are investigating topological states at the interface between dimer chains, characterized by a non-zero winding number. In order to exercise precise control over the polariton propagation, we study non-resonant laser excitation as well as resonant excitation in transmission geometry. The results highlight a new platform for the study of quantum fluids of light and non-linear optical propagation effects in coupled semiconductor waveguides.

Stability-Aware Training of Neural Network Interatomic Potentials with Differentiable Boltzmann Estimators
Sanjeev Raja, Ishan Amin, Fabian Pedregosa, Aditi S. Krishnapriyan
arXiv:2402.13984v1 Announce Type: cross Abstract: Neural network interatomic potentials (NNIPs) are an attractive alternative to ab-initio methods for molecular dynamics (MD) simulations. However, they can produce unstable simulations which sample unphysical states, limiting their usefulness for modeling phenomena occurring over longer timescales. To address these challenges, we present Stability-Aware Boltzmann Estimator (StABlE) Training, a multi-modal training procedure which combines conventional supervised training from quantum-mechanical energies and forces with reference system observables, to produce stable and accurate NNIPs. StABlE Training iteratively runs MD simulations to seek out unstable regions, and corrects the instabilities via supervision with a reference observable. The training procedure is enabled by the Boltzmann Estimator, which allows efficient computation of gradients required to train neural networks to system observables, and can detect both global and local instabilities. We demonstrate our methodology across organic molecules, tetrapeptides, and condensed phase systems, along with using three modern NNIP architectures. In all three cases, StABlE-trained models achieve significant improvements in simulation stability and recovery of structural and dynamic observables. In some cases, StABlE-trained models outperform conventional models trained on datasets 50 times larger. As a general framework applicable across NNIP architectures and systems, StABlE Training is a powerful tool for training stable and accurate NNIPs, particularly in the absence of large reference datasets.

Anderson Critical Metal Phase in Trivial States Protected by Average Magnetic Crystalline Symmetry
Fa-Jie Wang, Zhen-Yu Xiao, Raquel Queiroz, B. Andrei Bernevig, Ady Stern, Zhi-Da Song
arXiv:2306.04683v2 Announce Type: replace Abstract: Transitions between distinct obstructed atomic insulators (OAIs) protected by crystalline symmetries, where electrons form molecular orbitals centering away from the atom positions, must go through an intermediate metallic phase. In this work, we find that the intermediate metals will become a scale-invariant critical metal phase (CMP) under certain types of quenched disorder that respect the magnetic crystalline symmetries on average. We explicitly construct models respecting average $C_{2z}T$, $m$, and $C_{4z}T$ and show their scale-invariance under chemical potential disorder by the finite-size scaling method. Conventional theories, such as weak anti-localization and topological phase transition, cannot explain the underlying mechanism. A quantitative mapping between lattice and network models shows that the CMP can be understood through a semi-classical percolation problem. Ultimately, we systematically classify all the OAI transitions protected by (magnetic) groups $Pm$, $P2'$, $P4'$, and $P6'$ with and without spin-orbit coupling, most of which can support CMP.

Challenges in detecting topological superconducting transitions via supercurrent and phase probes in planar Josephson junctions
Pankaj Sharma, Narayan Mohanta
arXiv:2307.11645v2 Announce Type: replace Abstract: Topological superconductors harbor, at their boundaries and vortex cores, zero-energy Majorana bound states, which can be the building blocks in fault-tolerant topological quantum computing. Planar Josephson junctions host such topological superconducting phases, highly tunable by external magnetic field or phase difference between the superconducting leads. Despite many theoretical and experimental studies, the signatures of the transition to a topological superconducting phase, based on minima in the critical supercurrent $I_c$ flowing across the junction, $0$-$\pi$ transition in the ground state junction phase and their anisotropic magnetic-field response have remained unsettled. Using rigorous numerical calculations with several experimentally-relevant parameter settings, we show that $I_c$ and $\varphi_{_{\rm GS}}$ cannot indicate unambiguously topological transition in any realistic planar junctions. Furthermore, the anisotropic variations of $I_c$ and $\varphi_{_{\rm GS}}$ with in-plane magnetic field appear in junctions that are undoubtedly in trivial superconducting phase, raising concerns on the effectiveness of these probes in identifying topological transitions in planar junctions. We discuss possible strategies to confirm a topological superconducting phase in these platforms.

Disorder and diffuse scattering in single-chirality (TaSe$_4$)$_2$I crystals
Jacob A. Christensen, Simon Bettler, Kejian Qu, Jeffrey Huang, Soyeun Kim, Yinchuan Lu, Chengxi Zhao, Jin Chen, Matthew J. Krogstad, Toby J. Woods, Fahad Mahmood, Pinshane Y. Huang, Peter Abbamonte, Daniel P. Shoemaker
arXiv:2309.10236v5 Announce Type: replace Abstract: The quasi-one-dimensional chiral compound (TaSe$_4$)$_2$I has been extensively studied as a prime example of a topological Weyl semimetal. Upon crossing its phase transition temperature $T_\textrm{CDW}$ $\approx$ 263 K, (TaSe$_4$)$_2$I exhibits incommensurate charge density wave (CDW) modulations described by the well-defined propagation vector $\sim$(0.05, 0.05, 0.11), oblique to the TaSe$_4$ chains. Although optical and transport properties greatly depend on chirality, there is no systematic report about chiral domain size for (TaSe$_4$)$_2$I. In this study, our single-crystal scattering refinements reveal a bulk iodine deficiency, and Flack parameter measurements on multiple crystals demonstrate that separate (TaSe$_4$)$_2$I crystals have uniform handedness, supported by direct imaging and helicity dependent THz emission spectroscopy. Our single-crystal X-ray scattering and calculated diffraction patterns identify multiple diffuse features and create a real-space picture of the temperature-dependent (TaSe$_4$)$_2$I crystal structure. The short-range diffuse features are present at room temperature and decrease in intensity as the CDW modulation develops. These transverse displacements, along with electron pinning from the iodine deficiency, help explain why (TaSe$_4$)$_2$I behaves as an electronic semiconductor at temperatures above and below $T_\textrm{CDW}$, despite a metallic band structure calculated from density functional theory of the ideal structure.

Quantum theory of the magnetochiral anisotropy coefficient in ZrTe$_5$
Yi-Xiang Wang, Fuxiang Li
arXiv:2310.13909v3 Announce Type: replace Abstract: Recent experiments performed the nonreciprocal magneotransport in ZrTe$_5$ and obtained a giant magnetochiral anisotropy (MCA) coefficient $\gamma'$. The existing theoretical analysis was based on the semiclassical Boltzmann equation. In this paper, we develop a full quantum theory to calculate $\gamma'$ and further explore the underlying physics. We reveal that the $xz$-mirror symmetry breaking term also breaks the parity symmetry of the system and leads to mixed selection rules and nonvanishing second-order conductivity $\sigma_{xxx}$. The calculations show that $\gamma'$ decreases with the magnetic field, survives only to weak impurity scatterings, and exhibits a nonmonotonous dependence on the strength of the $xz$-mirror symmetry breaking. Our paper can provide a deeper insight into the intrinsic nonreciprocal magnetotransport phenomena in the topological semimetal material.

Symmetry-induced higher-order exceptional points in two dimensions
Anton Montag, Flore K. Kunst
arXiv:2401.10913v2 Announce Type: replace Abstract: Exceptional points of order $n$ (EP$n$s) appear in non-Hermitian systems as points where the eigenvalues and eigenvectors coalesce. They emerge if $2(n-1)$ real constraints are imposed, such that EP2s generically appear in two dimensions (2D). Symmetries that are local have been shown to reduce this number of constraints. In this work, we provide a complete characterization of the appearance of symmetry-induced higher-order EPs in 2D parameter space. We find that besides EP2s only EP3s, EP4s, and EP5s can be stabilized in 2D. Moreover, these higher-order EPs must always appear in pairs with their dispersion determined by the symmetries. Upon studying the complex spectral structure around these EPs, we find that depending on the symmetry, EP3s are accompanied by EP2 arcs, and 2- and 3-level open Fermi structures. Similarly, EP4s and closely related EP5s, which arise due to multiple symmetries, are accompanied by exotic EP arcs and open Fermi structures. For each case, we provide an explicit example. We also comment on the topological charge of these EPs, and discuss similarities and differences between symmetry-protected higher-order EPs and EP2s.

Understanding electronic excited states in BiFeO$_3$ via ab initio calculations and symmetry analysis
Aseem Rajan Kshirsagar, Sven Reichardt
arXiv:2402.05542v2 Announce Type: replace Abstract: BiFeO$_3$ is a technologically relevant multiferroic perovskite featuring ferroelectricity and antiferromagnetism. Its lattice, magnetic, and ferroelectric degrees of freedoms are coupled to its optically active excitations and thus hold the potential to be reversible probed and controlled by light. In this work, we combine ab initio density functional and many-body perturbation theory methods with an extensive symmetry and atomic-orbital analysis to describe and understand the electronic excited states spectrum and its imprint on the optical absorption spectrum with quantitative accuracy and qualitative insights. We find that the optical absorption spectrum of BiFeO$_3$ contain several strongly bound and spatially localized electronic transitions in which the spin-degree of freedom is almost fully flipped. With our analysis we thoroughly characterize these localized spin-flip transitions in terms of the unusual crystal field splitting of Fe-$3d$ single-electron orbitals. Our symmetry analysis further allows us to thoroughly explain how the spin content and the energetic fine structure of these strongly bound excitons are dictated by the interplay between crystal symmetry, electron-hole attraction, and the spin-orbit coupling.

Multiple asymmetric couplings induced unconventional corner mode in topolectrical circuits
Hengxuan Jiang, Xiumei Wang, Jie Chen, Xingping Zhou
arXiv:2402.12029v2 Announce Type: replace Abstract: We investigate the emergence of unconventional corner mode in a two-dimensional topolectrical circuits induced by asymmetric couplings. The non-Hermitian skin effect of two kinked one-dimensional lattices with multiple asymmetric couplings are explored. Then we extend to the two-dimensional model, derive conditions for the non-Hermitian hybrid skin effect and show how the corner modes are formed by non-reciprocal pumping based on one-dimensional topological modes. We provide explicit electrical circuit setups for realizing our observations via realistic LTspice simulation. Moreover, we show the time varying behaviors of voltage distributions to confirm our results. Our study may help to extend the knowledge on building the topological corner modes in the non-Hermitian presence.

Homotopical Foundations of Parametrized Quantum Spin Systems
Agnes Beaudry, Michael Hermele, Juan Moreno, Markus Pflaum, Marvin Qi, Daniel Spiegel
arXiv:2303.07431v2 Announce Type: replace-cross Abstract: In this paper, we present a homotopical framework for studying invertible gapped phases of matter from the point of view of infinite spin lattice systems, using the framework of algebraic quantum mechanics. We define the notion of quantum state types. These are certain lax-monoidal functors from the category of finite dimensional Hilbert spaces to the category of topological spaces. The universal example takes a finite dimensional Hilbert space to the pure state space of the quasi-local algebra of the quantum spin system with this Hilbert space at each site of a specified lattice. The lax-monoidal structure encodes the tensor product of states, which corresponds to stacking for quantum systems. We then explain how to formally extract parametrized phases of matter from quantum state types, and how they naturally give rise to $\mathscr{E}_\infty$-spaces for an operad we call the "multiplicative" linear isometry operad. We define the notion of invertible quantum state types and explain how the passage to phases for these is related to group completion. We also explain how invertible quantum state types give rise to loop-spectra. Our motivation is to provide a framework for constructing Kitaev's loop-spectrum of bosonic invertible gapped phases of matter. Finally, as a first step towards understanding the homotopy types of the loop-spectra associated to invertible quantum state types, we prove that the pure state space of any UHF algebra is simply connected.

Signature of (anti)cooperativity in the stochastic fluctuations of small systems: application to the bacterial flagellar motor
Mar\'ia-Jos\'e Franco-O\~nate, Andrea Parmeggiani, J\'er\^ome Dorignac, Fr\'ed\'eric Geniet, Jean-Charles Walter, Francesco Pedaci, Ashley L Nord, John Palmeri, Nils-Ole Walliser
arXiv:2307.00636v2 Announce Type: replace-cross Abstract: The cooperative binding of molecular agents onto a substrate is pervasive in living systems. To study whether a system shows cooperativity, one can rely on a fluctuation analysis of quantities such as the number of substrate-bound units and the residence time in an occupancy state. Since the relative standard deviation from the statistical mean monotonically decreases with the number of binding sites, these techniques are only suitable for small enough systems, such as those implicated in stochastic processes inside cells. Here, we present a general-purpose grand canonical Hamiltonian description of a small one-dimensional (1D) lattice gas with either nearest-neighbor or long-range interactions as prototypical examples of cooperativity-influenced adsorption processes. First, we elucidate how the strength and sign of the interaction potential between neighboring bound particles on the lattice determine the intensity of the fluctuations of the mean occupancy. We then employ this relationship to compare the theoretical predictions of our model to data from single molecule experiments on bacterial flagellar motors (BFM) of E. coli. In this way, we find evidence that cooperativity controls the mechano-sensitive dynamical assembly of the torque-generating units, the so-called stator units, onto the BFM. Furthermore, in an attempt to quantify fluctuations and the adaptability of the BFM, we estimate the stator-stator interaction potential. Finally, we conclude that the system resides in a sweet spot of the parameter space (phase diagram) suitable for a smoothly adaptive system while minimizing fluctuations.

Landau-Zener transition rates of superconducting qubits and absorption spectrum in quantum dots
Jorge G. Russo, Miguel Tierz
arXiv:2310.13058v3 Announce Type: replace-cross Abstract: New exact formulas are derived for systems involving Landau-Zener transition rates and for absorption spectra in quantum dots. These rectify previous inaccurate approximations utilized in experimental studies. The exact formulas give an explicit expression for the maxima and minima of the transition rate at any oscillating period and reveal a number of striking physical consequences, such as the suppression of oscillations for half-integer values of the detuning parameter and that the periodic dependence on the detuning parameter changes at special values of the driving field amplitude. The fluorescence spectra of quantum dots exhibit similar properties.

Breaking of a floating particle raft by water waves
Louis Saddier, Ambre Palotai, Matheo Aksil, Michel Tsamados, Michael Berhanu
arXiv:2310.16188v3 Announce Type: replace-cross Abstract: When particles of a few tens of microns are spread on the surface of water, they aggregate under the action of capillary forces and form a thin floating membrane, a particle raft. In a tank with a raft made of graphite powder, we generate in the laboratory gravity surface waves, whose wavelength {about 17 cm} is very large compared to the thickness of the raft {of order 10 microns}. For a sufficiently strong wave amplitude, the raft breaks up progressively by developing cracks and producing fragments whose sizes decrease on a time scale long compared to the period of the wave. We characterize the breaking mechanisms. Then, we investigate the area distribution of the fragments produced during the fragmentation process. The visual appearance of the fragments distributed in size and surrounded by open water bears a {notable} resemblance to the floes produced by the fracturing of sea ice by waves in the polar oceans. Fragmentation concepts and morphological tools built for sea ice floes can be applied to our macroscopic analog, on which the entire dynamic evolution is accessible. {However, the mechanic of the two systems differ, as our particle raft breaks due to the viscous stresses, whereas the sea-ice fractures due its bending by the waves.

Extended Baxter relations and QQ-systems for quantum affine algebras
Edward Frenkel, David Hernandez
arXiv:2312.13256v2 Announce Type: replace-cross Abstract: Generalized Baxter's TQ-relations and the QQ-system are systems of algebraic relations in the category O of representations of the Borel subalgebra of a quantum affine algebra U_q(g^), which we established in our earlier works arXiv:1308.3444 and arXiv:1606.05301. In the present paper, we conjecture a family of analogous relations labeled by elements of the Weyl group W of g, so that the original relations correspond to the identity element. These relations are closely connected to the W-symmetry of q-characters established in arXiv:2211.09779. We prove these relations for all w in W if g has rank two, and we prove the extended TQ-relations if w is a simple reflection. We also generalize our results and conjectures to the shifted quantum affine algebras.

Found 9 papers in prb
Date of feed: Thu, 22 Feb 2024 04:16:53 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)

Tuning magnetic interactions of Co and $4d$ transition-metal atomic bilayers on Re(0001) via interface engineering
Souvik Paul and Stefan Heinze
Author(s): Souvik Paul and Stefan Heinze

Employing ab initio density functional theory (DFT), we performed a systematic investigation of the electronic structure and the magnetic properties of atomic bilayers composed of a $4d$ transition-metal layer (Rh, Pd, and Ru) and a Co layer on the Re(0001) surface. Our DFT calculations reveal the i…

[Phys. Rev. B 109, 064417] Published Wed Feb 21, 2024

Topological quantum computation on a chiral Kondo chain
Tianhao Ren, Elio J. König, and Alexei M. Tsvelik
Author(s): Tianhao Ren, Elio J. König, and Alexei M. Tsvelik

This work describes a chiral Kondo chain model with symplectic symmetry. The authors demonstrate that it has a quantum critical ground state populated by non-Abelian anyons. Such a model is more robust than previously proposed models, and it can be experimentally implemented using hybrid quantum devices featuring superconducting islands coupled to chiral edges of topological insulators. Proposals for measurement-only anyonic quantum computations and error mitigations based on such a setup are provided.

[Phys. Rev. B 109, 075145] Published Wed Feb 21, 2024

Optical drive of amplitude and phase modes in excitonic insulators
Elahe Davari, S. Samaneh Ataei, and Mehdi Kargarian
Author(s): Elahe Davari, S. Samaneh Ataei, and Mehdi Kargarian

Motivated by recent interest in exploring excitonic condensate as the ground state of some narrow-band-gap semiconductors, such as transition metal dichalcogenides and layered chalcogenide material ${\mathrm{Ta}}_{2}{\mathrm{NiSe}}_{5}$, in this paper, we theoretically study the dynamics of condensa…

[Phys. Rev. B 109, 075146] Published Wed Feb 21, 2024

Layer-dependent transport properties in the moiré structure of strained homobilayer transition metal dichalcogenides
Chao-Jie Ren, Zhao Gong, Hui-Ying Mu, Xing-Tao An, Wang Yao, and Jian-Jun Liu
Author(s): Chao-Jie Ren, Zhao Gong, Hui-Ying Mu, Xing-Tao An, Wang Yao, and Jian-Jun Liu

Bilayer moiré structures have attracted significant attention recently due to their spatially modulated layer degrees of freedom. However, the layer-dependent transport mechanism in the moiré structures is still a problem to be explored. Here we investigate the layer-dependent transport properties r…

[Phys. Rev. B 109, 075424] Published Wed Feb 21, 2024

Spin preservation of a Ni adatom on amorphous graphene
Hongbo Du, Kaige Hu, Chongze Wang, Haifeng Li, Guohua Xu, Lingmin Yu, J. Cho, and Yu Jia
Author(s): Hongbo Du, Kaige Hu, Chongze Wang, Haifeng Li, Guohua Xu, Lingmin Yu, J. Cho, and Yu Jia

Two-dimensional amorphous materials can be regarded as electronic systems with a combination of amorphous and dimensional confinement effects that contributes to the discrete localized tail states near the Fermi level. In general, the magnetic properties of magnetic atoms may not be preserved upon d…

[Phys. Rev. B 109, 075425] Published Wed Feb 21, 2024

Tunneling optoresistance effect in two-dimensional modulated quantum structures
Sheng-Xiang Wang, Lai-Peng Luo, and Yong Guo
Author(s): Sheng-Xiang Wang, Lai-Peng Luo, and Yong Guo

Spin- and valley-resolved transport properties of a double beam off-resonant circular polarized light-modulated (CPL-modulated) junction based on monolayer transition-metal dichalcogenides (TMDc) are studied. We find that tuning between a high resistance configuration and a low resistance one can be…

[Phys. Rev. B 109, 085131] Published Wed Feb 21, 2024

Optical properties of Rydberg excitons in ${\mathrm{Cu}}_{2}\mathrm{O}$-based superlattices
David Ziemkiewicz, Gerard Czajkowski, and Sylwia Zielińska-Raczyńska
Author(s): David Ziemkiewicz, Gerard Czajkowski, and Sylwia Zielińska-Raczyńska

Combining the microscopic calculation of superlattice minibands and macroscopic real density matrix approach, one can obtain electric susceptibilities of the superlattice system irradiated by an electromagnetic wave. It is shown how to calculate the dispersion relation, excitonic resonance positions…

[Phys. Rev. B 109, 085309] Published Wed Feb 21, 2024

Photogalvanic effect induced by intervalley relaxation in a strained two-dimensional Dirac monolayer
A. V. Snegirev, V. M. Kovalev, and M. V. Entin
Author(s): A. V. Snegirev, V. M. Kovalev, and M. V. Entin

We theoretically study the photogalvanic effect in a strained two-dimensional transition-metal dichalcogenide monolayer due to deformation-induced lowering of the monolayer symmetry and electron-density difference in opposite valleys. This effect arises as a system response to a scalar nonequilibriu…

[Phys. Rev. B 109, 085422] Published Wed Feb 21, 2024

Electron-hole collision limited resistance of gapped graphene
Arseny Gribachov, Dmitry Svintsov, and Vladimir Vyurkov
Author(s): Arseny Gribachov, Dmitry Svintsov, and Vladimir Vyurkov

Collisions between electrons and holes can dominate the carrier scattering in clean graphene samples in the vicinity of the charge neutrality point. While electron-hole limited resistance in pristine gapless graphene is well studied, its evolution with induction of band gap ${E}_{g}$ is less explore…

[Phys. Rev. B 109, 085424] Published Wed Feb 21, 2024

Found 2 papers in prl
Date of feed: Thu, 22 Feb 2024 04:16:52 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)

Monofractality in the Solar Wind at Electron Scales: Insights from Kinetic Alfvén Waves Turbulence
Vincent David, Sébastien Galtier, and Romain Meyrand
Author(s): Vincent David, Sébastien Galtier, and Romain Meyrand

The breakdown of scale invariance in turbulent flows, known as multifractal scaling, is considered a cornerstone of turbulence. In solar wind turbulence, a monofractal behavior can be observed at electron scales, in contrast to larger scales where multifractality always prevails. Why scale invarianc…

[Phys. Rev. Lett. 132, 085201] Published Wed Feb 21, 2024

Mechanical Rippling for Diverse Ferroelectric Topologies in Otherwise Nonferroelectric ${\mathrm{SrTiO}}_{3}$ Nanofilms
Tao Xu, Chengsheng Wu, Sizheng Zheng, Yu Wang, Jie Wang, Hiroyuki Hirakata, Takayuki Kitamura, and Takahiro Shimada
Author(s): Tao Xu, Chengsheng Wu, Sizheng Zheng, Yu Wang, Jie Wang, Hiroyuki Hirakata, Takayuki Kitamura, and Takahiro Shimada

Polar topological structures such as skyrmions and merons have become an emerging research field due to their rich functionalities and promising applications in information storage. Up to now, the obtained polar topological structures are restricted to a few limited ferroelectrics with complex heter…

[Phys. Rev. Lett. 132, 086801] Published Wed Feb 21, 2024

Found 2 papers in science-adv
Date of feed: Wed, 21 Feb 2024 18:57:48 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)

Ochre-based compound adhesives at the Mousterian type-site document complex cognition and high investment
Patrick Schmidt, Radu Iovita, Armelle Charrié-Duhaut, Gunther Möller, Abay Namen, Ewa Dutkiewicz
Science Advances, Volume 10, Issue 8, February 2024.

Anomalous isotope effect on the optical bandgap in a monolayer transition metal dichalcogenide semiconductor
Yiling Yu, Volodymyr Turkowski, Jordan A. Hachtel, Alexander A. Puretzky, Anton V. Ievlev, Naseem U. Din, Sumner B. Harris, Vasudevan Iyer, Christopher M. Rouleau, Talat S. Rahman, David B. Geohegan, Kai Xiao
Science Advances, Volume 10, Issue 8, February 2024.

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)

Measuring entanglement entropy and its topological signature for phononic systems
< author missing >

Chiral and flat-band magnetic quasiparticles in ferromagnetic and metallic kagome layers
< author missing >