Found 33 papers in cond-mat
Date of feed: Wed, 24 May 2023 00:30:00 GMT

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Quantum state complexity meets many-body scars. (arXiv:2305.13322v1 [quant-ph])
Sourav Nandy, Bhaskar Mukherjee, Arpan Bhattacharyya, Aritra Banerjee

Scar eigenstates in a many-body system refers to a small subset of non-thermal finite energy density eigenstates embedded into an otherwise thermal spectrum. This novel non-thermal behaviour has been seen in recent experiments simulating a one-dimensional PXP model with a kinetically-constrained local Hilbert space realized by a chain of Rydberg atoms. We probe these small sets of special eigenstates starting from particular initial states by computing the spread complexity associated to time evolution of the PXP hamiltonian. Since the scar subspace in this model is embedded only loosely, the scar states form a weakly broken representation of the Lie Algebra. We demonstrate why a careful usage of the Forward Scattering Approximation (or similar strategies thereof) is required to extract an appropriate set of Lanczos coefficients in this case as the consequence of this approximate symmetry. This leads to a well defined notion of a closed Krylov subspace and consequently, that of spread complexity. We show how the spread complexity shows approximate revivals starting from both $|\mathbb{Z}_2\rangle$ and $|\mathbb{Z}_3\rangle$ states and how these revivals can be made more accurate by adding optimal perturbations to the bare Hamiltonian. We also investigate the case of the vacuum as the initial state, where revivals can be stabilized using an iterative process of adding few-body terms.

Bandwidth-tuned Wigner-Mott Transition at $\nu=1/5$: an Infinite Matrix Product State Study. (arXiv:2305.13355v1 [cond-mat.str-el])
Thomas G. Kiely, Debanjan Chowdhury

Electrons can organize themselves into charge-ordered states to minimize the effects of long-ranged Coulomb interactions. In the presence of a lattice, commensurability constraints lead to the emergence of incompressible Wigner-Mott (WM) insulators at various rational electron fillings, $\nu~=p/q$. The mechanism for quantum fluctuation-mediated melting of the WM insulators with increasing electron kinetic energy remains an outstanding problem. Here we analyze numerically the bandwidth-tuned transition out of the WM insulator at $\nu=1/5$ on infinite cylinders with varying circumference. For the two-leg ladder, the transition from the WM insulator to the Luttinger liquid proceeds via a distinct intermediate gapless phase -- the Luther-Emery liquid. We place these results in the context of a low-energy bosonization based theory for the transition. We also comment on the bandwidth-tuned transition(s) on the five-leg cylinder, and connections to ongoing experiments in dual-gated bilayer moir\'e transition metal dichalcogenide materials.

Stoner ferromagnetism in a momentum-confined interacting 2D electron gas. (arXiv:2305.13373v1 [cond-mat.str-el])
Ohad Antebi, Ady Stern, Erez Berg

In this work we investigate the ground state of a momentum-confined interacting 2D electron gas, a momentum-space analog of an infinite quantum well. The study is performed by combining analytical results with a numerical exact diagonalization procedure. We find a ferromagnetic ground state near a particular electron density and for a range of effective electron (or hole) masses. We argue that this observation may be relevant to the generalized Stoner ferromagnetism recently observed in multilayer graphene systems. The collective magnon excitations exhibit a linear dispersion, which originates from a diverging spin stiffness.

Quasi-Fermi liquid behavior in a one-dimensional system of interacting spinless fermions. (arXiv:2305.13374v1 [cond-mat.str-el])
Joshua D. Baktay, Alexander V. Rozhkov, Adrian E. Feiguin, Julian Rincon

We present numerical evidence for a new paradigm in one-dimensional interacting fermion systems, whose phenomenology has traits of both, Luttinger liquids and Fermi liquids. This new state, dubbed a quasi-Fermi liquid, possesses a discontinuity in its fermion occupation number at the Fermi momentum. The excitation spectrum presents particle-like quasiparticles, and absence of hole-like quasiparticles, giving rise instead to edge singularities. Such a state is realized in a one-dimensional spinless fermion lattice Hamiltonian by fine-tuning the interactions to a regime where they become irrelevant in the renormalization group sense. We show, using uniform infinite matrix products states and finite-entanglement scaling analysis, that the system ground state is characterized by a Luttinger parameter $K = 1$ and a discontinuous jump in the fermion occupation number. We support the characterization with calculations of the spectral function, that show a particle-hole asymmetry reflected in the existence of well-defined Landau quasiparticles above the Fermi level, and edge singularities without the associated quasiparticles below. These results indicate that the quasi-Fermi liquid paradigm can be realized beyond the low-energy perturbative realm.

Dependence of topological phase on nuclear spin $S$ and spin modulation vector in van der Waals Magnets. (arXiv:2305.13423v1 [cond-mat.mes-hall])
Kaushal K. Kesharpu

Recently non-chiral spin structures on the surface of the van der Waals (vdW) magnets have been observed down to monolayers. We provide a Hamiltonian to analyze the electronic properties of these materials. The Hamiltonian takes into account the arbitrary background spin structures and large atomic spin $S$ of the materials. The large spin-\emph{S} treatment is necessary as magnetic atoms of the vdW magnets can have spin $S > 1/2$. In this work the Hamiltonian is solved for the spin spirals with azimuthal and polar degrees of freedom -- this spin structure was recently observed in Fe$_{3}$GeTe$_{2}$. We methodically analyze the Hamiltonian for both integer and half-integer spins in the honeycomb lattice. It shows emerging topological hall effect emerges irrespective of the spin. The Chern number, hence the topological phase, depends on the spin \emph{S}, and interestingly only on the azimuthal angle of the spin vector. These results will be useful for the design of the topological electronics devices based on vdW magnets.

Anomalous tumbling of colloidal ellipsoids in Poiseuille flows. (arXiv:2305.13435v1 [cond-mat.soft])
Lauren E. Altman, Andrew D. Hollingsworth, David G. Grier

Shear flows cause aspherical colloidal particles to tumble so that their orientations trace out complex trajectories known as Jeffery orbits. The Jeffery orbit of a prolate ellipsoid is predicted to align the particle's principal axis preferentially in the plane transverse to the axis of shear. Holographic microscopy measurements reveal instead that colloidal ellipsoids' trajectories in Poiseuille flows strongly favor an orientation inclined by roughly $\pi/8$ relative to this plane. This anomalous observation is consistent with at least two previous reports of colloidal rods and dimers of colloidal spheres in Poiseuille flow and therefore appears to be a generic, yet unexplained feature of colloidal transport at low Reynolds numbers.

Superlattice Engineering of Topology in Massive Dirac Fermions. (arXiv:2305.13522v1 [cond-mat.mes-hall])
Nishchay Suri, Chong Wang, Benjamin M. Hunt, Di Xiao

We show that a superlattice potential can be employed to engineer topology in massive Dirac fermions in systems such as bilayer graphene, moir\'e graphene-boron nitride, and transition-metal dichalcogenide (TMD) monolayers and bilayers. We use symmetry analysis to analyze band inversions to determine the Chern number $\mathscr C$ for the valence band as a function of tunable potential parameters for a class of $C_4$ and $C_3$ symmetric potentials. We present a novel method to engineer Chern number $\mathscr{C}=2$ for the valence band and show that the applied potential at minimum must have a scalar together with a non-scalar periodic part. We discover that certain forms of the superlattice potential, which may be difficult to realize in naturally occurring moir\'e patterns, allow for the possibility of non-trivial topological transitions. These forms may be achievable using an external superlattice potential that can be created using contemporary experimental techniques. Our work paves the way to realize the quantum Spin Hall effect (QSHE), quantum anomalous Hall effect (QAHE), and even exotic non-Abelian anyons in the fractional quantum Hall effect (FQHE).

Current-driven motion of magnetic topological defects in ferromagnetic superconductors. (arXiv:2305.13564v1 [cond-mat.supr-con])
Se Kwon Kim, Suk Bum Chung

Recent years have seen a number of instances where magnetism and superconductivity intrinsically coexist. Our focus is on the case where spin-triplet superconductivity arises out of ferromagnetism, and we make a hydrodynamic analysis of the effect of a charge supercurrent on magnetic topological defects like domain walls and merons. We find that the emergent electromagnetic field that arises out of the superconducting order parameter provides a description for not only the physical quantities such as the local energy flux density and the interaction between current and defects but also the energy dissipation through magnetic dynamics of the Gilbert damping, which becomes more prominent compared to the normal state as superconductivity attenuates the energy dissipation through the charge sector. In particular, we reveal that the current-induced dynamics of domain walls and merons in the presence of the Gilbert damping give rise to the nonsingular $4\pi$ and $2\pi$ phase slips, respectively, revealing the intertwined dynamics of spin and charge degrees of freedom in ferromagnetic superconductors.

Gauge Field Induced Chiral Zero Mode in Five-dimensional Yang Monopole Metamaterials. (arXiv:2305.13566v1 [cond-mat.mes-hall])
Shaojie Ma, Hongwei Jia, Yangang Bi, Shangqiang Ning, Fuxin Guan, Hongchao Liu, Chenjie Wang, Shuang Zhang

Owing to the chirality of Weyl nodes characterized by the first Chern number, a Weyl system supports one-way chiral zero modes under a magnetic field, which underlies the celebrated chiral anomaly. As a generalization of Weyl nodes from three-dimensional to five-dimensional physical systems, Yang monopoles are topological singularities carrying nonzero second-order Chern numbers c2 = +1 or -1. Here, we couple a Yang monopole with an external gauge field using an inhomogeneous Yang monopole metamaterial, and experimentally demonstrate the existence of a gapless chiral zero mode, where the judiciously designed metallic helical structures and the corresponding effective antisymmetric bianisotropic terms provide the means for controlling gauge fields in a synthetic five-dimensional space. This zeroth mode is found to originate from the coupling between the second Chern singularity and a generalized 4-form gauge field - the wedge product of the magnetic field with itself. This generalization reveals intrinsic connections between physical systems of different dimensions, while a higher dimensional system exhibits much richer supersymmetric structures in Landau level degeneracy due to the internal degrees of freedom. Our study offers the possibility of controlling electromagnetic waves by leveraging the concept of higher-order and higher-dimensional topological phenomena.

From Ergodicity to Many-Body Localization in a One-Dimensional Interacting Non-Hermitian Stark System. (arXiv:2305.13636v1 [cond-mat.dis-nn])
Jinghu Liu, Zhihao Xu

Recent studies on disorder-induced many-body localization (MBL) in non-Hermitian quantum systems have attracted great interest. However, the non-Hermitian disorder-free MBL still needs to be clarified. We consider a one-dimensional interacting Stark model with nonreciprocal hoppings having time-reversal symmetry, the properties of which are boundary dependent. Under periodic boundary conditions (PBC), such a model exhibits three types of phase transitions: the real-complex transition of eigenenergies, the topological phase transition, and the non-Hermitian Stark MBL transition. The real-complex and topological phase transitions occur at the same point in the thermodynamic limit, but do not coincide with the non-Hermitian Stark MBL transition, which is quite different from the non-Hermitian disordered cases. By the level statistics, the system undergoes from the Ginibre ensemble (GE) to Gaussian orthogonal ensemble (GOE) to Possion ensemble (PE) transitions with the increase of the linear tilt potential's strength $\gamma$. The real-complex transition of the eigenvalues is accompanied by the GE-to-GOE transition in the ergodic regime. Moreover, the second transition of the level statistics corresponds to the occurrence of non-Hermitian Stark MBL. We demonstrate that the non-Hermitian Stark MBL is robust and shares many similarities with disorder-induced MBL, which several existing characteristic quantities of the spectral statistics and eigenstate properties can confirm. The dynamical evolutions of the entanglement entropy and the density imbalance can distinguish the real-complex and Stark MBL transitions. Finally, we find that our system under open boundary conditions lacks a real-complex transition, and the transition of non-Hermitian Stark MBL is the same as that under PBCs.

Built-in electric field and strain tunable valley-related multiple topological phase transitions in VSiXN$_4$ (X= C, Si, Ge, Sn, Pb) monolayers. (arXiv:2305.13670v1 [cond-mat.mes-hall])
Ping Li, Xiao Yang, Qing-Song Jiang, Yin-Zhong Wu, Wei Xun

The valley-related multiple topological phase transitions attracted significant attention due to their providing significant opportunities for fundamental research and practical applications. However, unfortunately, to date there is no real material that can realize valley-related multiple topological phase transitions. Here, through first-principles calculations and model analysis, we investigate the structural, magnetic, electronic, and topological properties of VSiXN$_4$ (X = C, Si, Ge, Sn, Pb) monolayers. VSiXN$_4$ monolayers are stable and intrinsically ferrovalley materials. Intriguingly, we found that the built-in electric field and strain can induce valley-related multiple topological phase transitions in the materials from valley semiconductor to valley-half-semimetal, to valley quantum anomalous Hall insulator, to valley-half-semimetal, and to valley semiconductor (or to valley-metal). The nature of topological phase transition is the built-in electric field and strain induce band inversion between the d$_{xy}$/d$_{x2-y2}$ and d$_{z2}$ at obritals at K and K' valleys. Our findings not only reveal the mechanism of multiple topological phase transitions, but also provides an ideal platform for the multi-field manipulating the spin, valley, and topological physics. It will open new perspectives for spintronic, valleytronic, and topological nanoelectronic applications based on these materials.

Detecting, distinguishing, and spatiotemporally tracking photogenerated charge and heat at the nanoscale. (arXiv:2305.13676v1 [cond-mat.mtrl-sci])
Hannah L. Weaver, Cora M. Went, Joeson Wong, Dipti Jasrasaria, Eran Rabani, Harry A. Atwater, Naomi S. Ginsberg

Since dissipative processes are ubiquitous in semiconductors, characterizing how electronic and thermal energy transduce and transport at the nanoscale is vital for understanding and leveraging their fundamental properties. For example, in low-dimensional transition metal dichalcogenides (TMDCs), excess heat generation upon photoexcitation is difficult to avoid since even with modest injected exciton densities, exciton-exciton annihilation still occurs. Both heat and photoexcited electronic species imprint transient changes in the optical response of a semiconductor, yet the unique signatures of each are difficult to disentangle in typical spectra due to overlapping resonances. In response, we employ stroboscopic optical scattering microscopy (stroboSCAT) to simultaneously map both heat and exciton populations in few-layer \ch{MoS2} on relevant nanometer and picosecond length- and time scales and with 100-mK temperature sensitivity. We discern excitonic contributions to the signal from heat by combining observations close to and far from exciton resonances, characterizing photoinduced dynamics for each. Our approach is general and can be applied to any electronic material, including thermoelectrics, where heat and electronic observables spatially interplay, and lays the groundwork for direct and quantitative discernment of different types of coexisting energy without recourse to complex models or underlying assumptions.

Electromagnetic response of the surface states of a topological insulator nanowire embedded within a resonator. (arXiv:2305.13744v1 [cond-mat.mes-hall])
Shimon Arie Haver, Eran Ginossar, Sebastian E. de Graaf, Eytan Grosfeld

Exploring the interplay between topological phases and photons opens new avenues for investigating novel quantum states. Here we show that superconducting resonators can serve as sensitive probes for properties of topological insulator nanowires (TINWs) embedded within them. By combining a static, controllable magnetic flux threading the TINW with an additional oscillating electromagnetic field applied perpendicularly, we show that orbital resonances can be generated and are reflected in periodic changes of the Q-factor of the resonator as a function of the flux. This response probes the confinement of the two-dimensional Dirac orbitals on the surface of the TINW, revealing their density of states and specific transition rules, as well as their dependence on the applied flux. Our approach represents a promising cross-disciplinary strategy for probing topological solid-state materials using state-of-the-art photonic cavities, which would avoid the need for attaching contacts, thereby enabling access to electronic properties closer to the pristine topological states.

Quantum Interference by Vortex Supercurrents. (arXiv:2305.13952v1 [cond-mat.supr-con])
G. P. Papari, V. M. Fomin

We analyze the origin of the parabolic background of magnetoresistance oscillations measured in finite-width superconducting mesoscopic rings with input and output stubs and in patterned films. The transmission model explaining the sinusoidal oscillation of magnetoresistance is extended to address the parabolic background as a function of the magnetic field. Apart from the interference mechanism activated by the ring, pinned superconducting vortices as topological defects introduce a further interference-based distribution of supercurrents that affects, in turn, the voltmeter-sensed quasiparticles. The onset of vortices changes the topology of the superconducting state in a mesoscopic ring in a such a way that the full magnetoresistance dynamics can be interpreted owing to the interference of the constituents of the order parameter induced by both the ring with its doubly-connected topology and the vortex lattice in it.

Threshold cascade dynamics on coevolving networks. (arXiv:2305.13965v1 [physics.soc-ph])
Byungjoon Min, Maxi San Miguel

We study the coevolutionary dynamics of network topology and social complex contagion using a threshold cascade model. Our coevolving threshold model incorporates two mechanisms: the threshold mechanism for the spreading of a minority state such as a new opinion, idea, or innovation and the network plasticity implemented as rewiring of links to cut the connections between nodes in different states. Using numerical simulations and a mean-field theoretical analysis, we demonstrate that the coevolutionary dynamics can significantly affect the cascades dynamics. The domain of parameters, i.e., threshold and network mean degree, for which global cascades occur shrinks with increasing network plasticity, indicating that the rewiring process suppresses the onset of global cascades. We also found that during evolution, non-adopted nodes form denser connections, resulting in a wider degree distribution and a non-monotonous dependence of cascades sizes with plasticity.

Long-range correlation-induced effects at high-order harmonic generation on graphene quantum dots. (arXiv:2305.14034v1 [cond-mat.mes-hall])
H.K. Avetissian, A.G. Ghazaryan, Kh.V. Sedrakian, G.F. Mkrtchian

This paper focuses on investigating high-order harmonic generation (HHG) in graphene quantum dots (GQDs) under intense near-infrared laser fields. To model the GQD and its interaction with the laser field, we utilize a mean-field approach. Our analysis of the HHG power spectrum reveals fine structures and a noticeable enhancement in cutoff harmonics due to the long-range correlations. We also demonstrate the essential role of Coulomb interaction in determining of harmonics intensities and cutoff position. Unlike atomic HHG, where the cutoff energy is proportional to the pump wave intensity, in GQDs the cutoff energy scales with the square root of the field strength amplitude. A detailed time-frequency analysis of the entire range of HHG spectrum is presented using a wavelet transform. The analysis reveals intricate details of the spectral and temporal fine structures of HHG, offering insights into the various HHG mechanisms in GQDs.

Laser-based angle-resolved photoemission spectroscopy with micrometer spatial resolution and detection of three-dimensional spin vector. (arXiv:2305.14052v1 [cond-mat.mtrl-sci])
Takuma Iwata, T. Kousa, Y. Nishioka, K. Ohwada, Kenta Kuroda, H. Iwasawa, M. Arita, S. Kumar, A. Kimura, K. Miyamoto, T. Okuda

We have developed a state-of-the-art apparatus for laser-based spin- and angle-resolved photoemission spectroscopy with micrometer spatial resolution (micro-SARPES). This equipment is achieved through the combination of a high-resolution photoelectron spectrometer, a 6-eV laser with high photon flux that is focused down to a few micrometers, a high-precision sample stage control system, and a double very-low-energy-electron-diffraction spin detector. The setup achieves an energy resolution of 1.5 (5.5) meV without (with) the spin detection mode, compatible with a spatial resolution better than 10 micrometers. This enables us to probe both spatially-resolved electronic structures and vector information of spin polarization in three dimensions. The performance of micro-SARPES apparatus is demonstrated by presenting ARPES and SARPES results from topological insulators and Au photolithography patterns on a Si (001) substrate.

Enriched string-net models and their excitations. (arXiv:2305.14068v1 [cond-mat.str-el])
David Green, Peter Huston, Kyle Kawagoe, David Penneys, Anup Poudel, Sean Sanford

Boundaries of Walker-Wang models have been used to construct commuting projector models which realize chiral unitary modular tensor categories (UMTCs) as boundary excitations. Given a UMTC $\mathcal{A}$ representing the Witt class of an anomaly, the article [arXiv:2208.14018] gave a commuting projector model associated to an $\mathcal{A}$-enriched unitary fusion category $\mathcal{X}$ on a 2D boundary of the 3D Walker-Wang model associated to $\mathcal{A}$. That article claimed that the boundary excitations were given by the enriched center/M\"uger centralizer $Z^\mathcal{A}(\mathcal{X})$ of $\mathcal{A}$ in $Z(\mathcal{X})$.

In this article, we give a rigorous treatment of this 2D boundary model, and we verify this assertion using topological quantum field theory (TQFT) techniques, including skein modules and a certain semisimple algebra whose representation category describes boundary excitations. We also use TQFT techniques to show the 3D bulk point excitations of the Walker-Wang bulk are given by the M\"uger center $Z_2(\mathcal{A})$, and we construct bulk-to-boundary hopping operators $Z_2(\mathcal{A})\to Z^{\mathcal{A}}(\mathcal{X})$ reflecting how the UMTC of boundary excitations $Z^{\mathcal{A}}(\mathcal{X})$ is symmetric-braided enriched in $Z_2(\mathcal{A})$.

This article also includes a self-contained comprehensive review of the Levin-Wen string net model from a unitary tensor category viewpoint, as opposed to the skeletal $6j$ symbol viewpoint.

Mean field theory of chaotic insect swarms. (arXiv:2305.14085v1 [cond-mat.stat-mech])
R. González-Albaladejo, L. L. Bonilla

The harmonically confined Vicsek model displays qualitative and quantitative features observed in natural insect swarms. It exhibits a scale free transition between single and multicluster chaotic phases. Finite size scaling indicates that this unusual phase transition occurs at zero confinement [Physical Review E 107, 014209 (2023)]. While the evidence of the scale-free-chaos phase transition comes from numerical simulations, here we present its mean field theory. Analytically determined critical exponents are those of the Landau theory of equilibrium phase transitions plus dynamical critical exponent $z=1$ and a new critical exponent $\varphi=0.5$ for the largest Lyapunov exponent. The phase transition occurs at zero confinement and noise in the mean field theory. The noise line of zero largest Lyapunov exponents informs observed behavior: (i) the qualitative shape of the swarm (on average, the center of mass rotates slowly at the rate marked by the winding number and its trajectory fills compactly the space, similarly to the observed condensed nucleus surrounded by vapor), and (ii) the critical exponents resemble those observed in natural swarms. Our predictions include power laws for the frequency of the maximal spectral amplitude and the winding number.

Topological nature of the proper spin current and the spin-Hall torque. (arXiv:2305.14108v1 [cond-mat.mes-hall])
Hong Liu, James H. Cullen, Dimitrie Culcer

Spin currents driven by spin-orbit coupling are key to spin torque devices, but determining the proper spin current is highly non-trivial. Here we derive a general quantum-mechanical formula for the intrinsic proper spin current showing that it is a topological quantity, and can be finite even in the gap. We determine the spin-Hall current due to the bulk states of topological insulators both deep in the bulk, where the system is unmagnetized, and near the interface, where a proximity-induced magnetization is present, as well as for low-dimensional spin-3/2 hole systems.

A Jastrow wave function for the spin-1 Heisenberg chain: the string order revealed by the mapping to the classical Coulomb gas. (arXiv:2305.14162v1 [cond-mat.str-el])
Davide Piccioni, Christian Apostoli, Federico Becca, Guglielmo Mazzola, Alberto Parola, Sandro Sorella, Giuseppe E. Santoro

We show that a two-body Jastrow wave function is able to capture the ground-state properties of the $S=1$ antiferromagnetic Heisenberg chain with the single-ion anisotropy term, in both the topological and trivial phases. Here, the optimized Jastrow pseudo potential assumes a very simple form in Fourier space, i.e., $v_{q} \approx 1/q^2$, which is able to give rise to a finite string-order parameter in the topological regime. The results are analysed by using an exact mapping from the quantum expectation values over the variational state to the classical partition function of the one-dimensional Coulomb gas of particles with charge $q=\pm 1$. Here, two phases are present at low temperatures: the first one is a diluted gas of dipoles (bound states of particles with opposite charges), which are randomly oriented (describing the trivial phase); the other one is a dense liquid of dipoles, which are aligned thanks to the residual dipole-dipole interactions (describing the topological phase, with the finite string order being related to the dipole alignment). Our results provide an insightful interpretation of the ground-state nature of the spin-1 antiferromagnetic Heisenberg model.

Refraction laws for two-dimensional plasmons. (arXiv:2305.14266v1 [physics.optics])
Dmitry Svintsov, Georgy Alymov

Despite numerous applications of two-dimensional plasmons for electromagnetic energy manipulation at the nanoscale, their quantitative refraction and reflection laws (analogs of Fresnel formulas in optics) have not yet been established. This fact can be traced down to the strong non-locality of equations governing the 2d plasmon propagation. Here, we tackle this difficulty by direct solution of plasmon scattering problem with Wiener-Hopf technique. We obtain the reflection and transmission coefficients for 2d plasmons at the discontinuity of 2d conductivity at arbitrary incidence angle, for both gated and non-gated 2d systems. At a certain incidence angle, the absolute reflectivity has a pronounced dip reaching zero for gated plasmons. The dip is associated with wave passage causing no dynamic charge accumulation at the boundary. For all incidence angles, the reflection has a non-trivial phase different from zero and $\pi$.

Emergent correlated phases in rhombohedral trilayer graphene induced by proximity spin-orbit and exchange coupling. (arXiv:2305.14277v1 [cond-mat.str-el])
Yaroslav Zhumagulov, Denis Kochan, Jaroslav Fabian

The impact of proximity-induced spin-orbit and exchange coupling on the correlated phase diagram of rhombohedral trilayer graphene (RTG) is investigated theoretically. By employing \emph{ab initio}-fitted effective models of RTG encapsulated by transition metal dichalcogenides (spin-orbit proximity effect) and ferromagnetic Cr$_2$Ge$_2$Te$_6$ (exchange proximity effect), we incorporate the Coulomb interactions within the random-phase approximation to explore potential correlated phases at different displacement field and doping. We find a rich spectrum of spin-valley resolved Stoner and intervalley coherence instabilities induced by the spin-orbit proximity effects, such as the emergence of a \textit{spin-valley-coherent} phase due to the presence of valley-Zeeman coupling. Similarly, proximity exchange removes the phase degeneracies by biasing the spin direction, enabling a magneto-correlation effect -- strong sensitivity of the correlated phases to the relative magnetization orientations (parallel or antiparallel) of the encapsulating ferromagnetic layers.

Transport properties of hybrid single-bilayer graphene interfaces in magnetic field. (arXiv:2305.14284v1 [cond-mat.mes-hall])
Nadia Benlakhouy, Ahmed Jellal, Michael Schreiber

The electronic properties of a hybrid system made of single-bilayer graphene structures subjected to a perpendicular magnetic field are studied for the zigzag boundaries of the junction, zigzag-1 (ZZ1) and zigzag-2 (ZZ2). These later examples exhibit different behaviors that have been investigated using the continuum Dirac model. Our results reveal that the conductance depends on the width of bilayer graphene for ZZ1 and shows maxima for ZZ2 as a function of the magnetic field, in contrast to ZZ1. It is found that interfaces have significant impacts on the transmission probability, with the confinement of the ZZ1 boundary being more substantial than that of ZZ2

Disentangling stress and curvature effects in layered 2D ferroelectric CuInP2S6. (arXiv:2305.14309v1 [cond-mat.mtrl-sci])
Yongtao Liu, Anna N. Morozovska, Ayana Ghosh, Kyle P. Kelley, Eugene A. Eliseev, Jinyuan Yao, Ying Liu, Sergei V. Kalinin

Nanoscale ferroelectric 2D materials offer unique opportunity to investigate curvature and strain effects on materials functionalities. Among these, CuInP2S6 (CIPS) has attracted tremendous research interest in recent years due to combination of room temperature ferroelectricity, scalability to a few layers thickness, and unique ferrielectric properties due to coexistence of 2 polar sublattices. Here, we explore the local curvature and strain effect on the polarization in CIPS via piezoresponse force microscopy and spectroscopy. To explain the observed behaviors and decouple the curvature and strain effects in 2D CIPS, we introduce finite element Landau-Ginzburg-Devonshire model. The results show that bending induces ferrielectric domains in CIPS, and the polarization-voltage hysteresis loops differ in bending and non-bending regions. Our simulation indicates that the flexoelectric effect can affect local polarization hysteresis. These studies open a novel pathway for the fabrication of curvature-engineered nanoelectronic devices.

Majorana zero modes in gate-defined germanium hole nanowires. (arXiv:2305.14313v1 [cond-mat.mes-hall])
Katharina Laubscher, Jay D. Sau, Sankar Das Sarma

We theoretically study gate-defined one-dimensional channels in planar Ge hole gases as a potential platform for non-Abelian Majorana zero modes. We model the valence band holes in the Ge channel by adding appropriate confinement potentials to the 3D Luttinger-Kohn Hamiltonian, additionally taking into account a magnetic field applied parallel to the channel, an out-of-plane electric field, as well as the effect of compressive strain in the parent quantum well. Assuming that the Ge channel is proximitized by an $s$-wave superconductor (such as, e.g., Al) we calculate the topological phase diagrams for different channel geometries, showing that sufficiently narrow Ge hole channels can indeed enter a topological superconducting phase with Majorana zero modes at the channel ends. We estimate the size of the topological gap and its dependence on various system parameters such as channel width, strain, and the applied out-of-plane electric field, allowing us to critically discuss under which conditions Ge hole channels may manifest Majorana zero modes. Since ultra-clean Ge quantum wells with hole mobilities exceeding one million and mean-free paths on the order of many microns already exist, gate-defined Ge hole channels may be able to overcome some of the problems caused by the presence of substantial disorder in more conventional Majorana platforms.

Localization of generalized Wannier bases implies Chern triviality in non-periodic insulators. (arXiv:2012.14407v2 [math-ph] UPDATED)
Giovanna Marcelli, Massimo Moscolari, Gianluca Panati

We investigate the relation between the localization of generalized Wannier bases and the topological properties of two-dimensional gapped quantum systems of independent electrons in a disordered background, including magnetic fields, as in the case of Chern insulators and quantum Hall systems. We prove that the existence of a well-localized generalized Wannier basis for the Fermi projection implies the vanishing of the Chern character, which is proportional to the Hall conductivity in the linear response regime. Moreover, we state a localization dichotomy conjecture for general non-periodic gapped quantum systems.

Polymer stretching in laminar and random flows: entropic characterization. (arXiv:2112.01344v2 [cond-mat.soft] UPDATED)
Stefano Musacchio, Victor Steinberg, Dario Vincenzi

Polymers in nonuniform flows undergo strong deformation, which in the presence of persistent stretching can result in the coil-stretch transition. This phenomenon has been characterized by using the formalism of nonequilibrium statistical mechanics. In particular, the entropy of the polymer extension reaches a maximum at the transition. We extend the entropic characterization of the coil-stretch transition by studying the differential entropy of the polymer fractional extension in a set of laminar and random velocity fields that are benchmarks for the study of polymer stretching in flow. In the case of random velocity fields, a suitable description of the transition is obtained by considering the entropy of the logarithm of the extension instead of the entropy of the extension itself. Entropy emerges as an effective tool for capturing the coil-stretch transition and comparing its features in different flows.

When Superconductivity Crosses Over: From BCS to BEC. (arXiv:2208.01774v3 [cond-mat.supr-con] UPDATED)
Qijin Chen, Zhiqiang Wang, Rufus Boyack, Shuolong Yang, K. Levin

New developments in superconductivity, particularly through unexpected and often astonishing forms of superconducting materials, continue to excite the community and stimulate theory. It is now becoming clear that there are two distinct platforms for superconductivity through natural and synthetic materials. Indeed, the latter category has greatly expanded in the last decade or so, with the discoveries of new forms of superfluidity in artificial heterostructures and the exploitation of proximitization. The former category continues to surprise through the Fe-based pnictides and chalcogenides, and nickelates as well as others. It is the goal of this review to present this two-pronged investigation into superconductors, with a focus on those which we have come to understand belong somewhere between the BCS and Bose-Einstein condensation (BEC) regimes. We characterize in detail the nature of this ``crossover" superconductivity, which is to be distinguished from crossover superfluidity in Fermi gases. In the process, we address the multiple ways of promoting a system out of the BCS and into the BCS-BEC crossover regime within the context of concrete experimental realizations. These involve natural materials, such as organic conductors, as well as artificial, mostly two-dimensional materials, such as magic-angle twisted bilayer and trilayer graphene, or gate-controlled devices, as well as one-layer and interfacial superconducting films. This work should be viewed as a celebration of BCS theory by showing that even though this theory was initially implemented with the special case of weak correlations in mind, it can in a very natural way be extended to treat the case of these more exotic strongly correlated superconductors.

Enhanced robustness and dimensional crossover of superradiance in cuboidal nanocrystal superlattices. (arXiv:2209.10943v2 [cond-mat.mes-hall] UPDATED)
Sushrut Ghonge, David Engel, Francesco Mattiotti, G. Luca Celardo, Masaru Kuno, Boldizsár Jankó

Cooperative emission of coherent radiation from multiple emitters (known as superradiance) has been predicted and observed in various physical systems, most recently in CsPbBr$_3$ nanocrystal superlattices. Superradiant emission is coherent and occurs on timescales faster than the emission from isolated nanocrystals. Theory predicts cooperative emission being faster by a factor of up to the number of nanocrystals ($N$). However, superradiance is strongly suppressed due to the presence of energetic disorder, stemming from nanocrystal size variations and thermal decoherence. Here, we analyze superradiance from superlattices of different dimensionalities (one-, two- and three-dimensional) with variable nanocrystal aspect ratios. We predict as much as a 15-fold enhancement in robustness against realistic values of energetic disorder in three-dimensional (3D) superlattices composed of cuboid-shaped, as opposed to cube-shaped, nanocrystals. Superradiance from small $(N\lesssim 10^3)$ two-dimensional (2D) superlattices is up to ten times more robust to static disorder and up to twice as robust to thermal decoherence than 3D superlattices with the same $N$. As the number of $N$ increases, a crossover in the robustness of superradiance occurs from 2D to 3D superlattices. For large $N\ (> 10^3)$, the robustness in 3D superlattices increases with $N$, showing cooperative robustness to disorder. This opens the possibility of observing superradiance even at room temperature in large 3D superlattices, if nanocrystal size fluctuations can be kept small.

Quasi-equilibrium polariton condensates in the non-linear regime and beyond. (arXiv:2211.03321v2 [cond-mat.mes-hall] UPDATED)
Ned Goodman, Brendan C. Mulkerin, Jesper Levinsen, Meera M. Parish

We investigate the many-body behavior of polaritons formed from electron-hole pairs strongly coupled to photons in a two-dimensional semiconductor microcavity. We use a microscopic mean-field BCS theory that describes polariton condensation in quasi-equilibrium across the full range of excitation densities. In the limit of vanishing density, we show that our theory recovers the exact single-particle properties of polaritons, while at low densities it captures non-linear polariton-polariton interactions within the Born approximation. For the case of highly screened contact interactions between charge carriers, we obtain analytic expressions for the equation of state of the many-body system. This allows us to show that there is a photon resonance at a chemical potential higher than the photon cavity energy, where the electron-hole pair correlations in the polariton condensate become universal and independent of the details of the carrier interactions. Comparing the effect of different ranged interactions between charge carriers, we find that the Rytova-Keldysh potential (relevant to transition metal dichalcogenides) offers the best prospect of reaching the BCS regime, where pairs strongly overlap and the minimum pairing gap occurs at finite momentum. Finally, going beyond thermal equilibrium, we argue that there are generically two polariton branches in the driven-dissipative system and we discuss the possibility of a density-driven exceptional point within our model.

Detecting charge transfer at defects in 2D materials with electron ptychography. (arXiv:2301.04469v3 [cond-mat.mtrl-sci] UPDATED)
Christoph Hofer, Jacob Madsen, Toma Susi, Timothy J. Pennycook

Charge transfer between atoms is fundamental to chemical bonding but has remained very challenging to detect directly in real space. Atomic-resolution imaging of charge density is not sufficient by itself, as the change in the density due to bonding is subtle compared to the total local charge density. Both sufficiently high sensitivity and accuracy are required, which we demonstrate here for the detection of charge transfer at defects in two-dimensional WS\textsubscript{2} via high-speed electron ptychography and its ability to correct errors due to residual lens aberrations.

Comparative Electronic Structures of the Chiral Helimagnets Cr1/3NbS2 and Cr1/3TaS2. (arXiv:2305.08829v2 [cond-mat.mtrl-sci] UPDATED)
Lilia S. Xie, Oscar Gonzalez, Kejun Li, Matteo Michiardi, Sergey Gorovikov, Sae Hee Ryu, Shannon S. Fender, Marta Zonno, Na Hyun Jo, Sergey Zhdanovich, Chris Jozwiak, Aaron Bostwick, Samra Husremovic, Matthew P. Erodici, Cameron Mollazadeh, Andrea Damascelli, Eli Rotenberg, Yuan Ping, D. Kwabena Bediako

Magnetic materials with noncollinear spin textures are promising for spintronic applications. To realize practical devices, control over the length and energy scales of such spin textures is imperative. The chiral helimagnets Cr1/3NbS2 and Cr1/3TaS2 exhibit analogous magnetic phase diagrams with different real-space periodicities and field dependence, positioning them as model systems for studying the relative strengths of the microscopic mechanisms giving rise to exotic spin textures. Here, we carry out a comparative study of the electronic structures of Cr1/3NbS2 and Cr1/3TaS2 using angle-resolved photoemission spectroscopy and density functional theory. We show that bands in Cr1/3TaS2 are more dispersive than their counterparts in Cr1/3NbS2 and connect this result to bonding and orbital overlap in these materials. We also unambiguously distinguish exchange splitting from surface termination effects by studying the dependence of their photoemission spectra on polarization, temperature, and beam size. We find strong evidence that hybridization between intercalant and host lattice electronic states mediates the magnetic exchange interactions in these materials, suggesting that band engineering is a route toward tuning their spin textures. Overall, these results underscore how the modular nature of intercalated transition metal dichalcogenides translates variation in composition and electronic structure to complex magnetism.

Found 9 papers in prb
Date of feed: Wed, 24 May 2023 03:17:13 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]+)

Emergence of large spin-charge interconversion at an oxidized Cu/W interface
Inge Groen, Van Tuong Pham, Stefan Ilić, Andrey Chuvilin, Won Young Choi, Edurne Sagasta, Diogo C. Vaz, Isabel C. Arango, Nerea Ontoso, F. Sebastian Bergeret, Luis E. Hueso, Ilya V. Tokatly, and Fèlix Casanova
Author(s): Inge Groen, Van Tuong Pham, Stefan Ilić, Andrey Chuvilin, Won Young Choi, Edurne Sagasta, Diogo C. Vaz, Isabel C. Arango, Nerea Ontoso, F. Sebastian Bergeret, Luis E. Hueso, Ilya V. Tokatly, and Fèlix Casanova

Spin-orbitronic devices can integrate memory and logic by exploiting spin-charge interconversion (SCI), which is optimized by design and materials selection. In these devices, interfaces are crucial elements as they can prohibit or promote spin flow in a device as well as possess spin-orbit coupling…

[Phys. Rev. B 107, 184438] Published Tue May 23, 2023

Twist-angle dependent proximity induced spin-orbit coupling in graphene/topological insulator heterostructures
Thomas Naimer and Jaroslav Fabian
Author(s): Thomas Naimer and Jaroslav Fabian

The authors investigate the proximity-induced spin-orbit coupling in twisted graphene/topological insulator (Bi2Se3 and Bi2Te3) heterostructures from first principles. Fitting the band structures around the graphene Dirac cone to an established spin-orbit Hamiltonian yields the twist angle dependencies of the spin-orbit couplings. Amongst other findings, an interesting form of the Rashba spin-orbit coupling arises for such structures. It entails a large radial component of the in-plane spin structure around the Dirac cone, which can be used to realize collinear charge-to-spin conversion.

[Phys. Rev. B 107, 195144] Published Tue May 23, 2023

Magnetic excitations in the topological semimetal ${\mathrm{YbMnSb}}_{2}$
Siobhan M. Tobin, Jian-Rui Soh, Hao Su, Andrea Piovano, Anne Stunault, J. Alberto Rodríguez-Velamazán, Yanfeng Guo, and Andrew T. Boothroyd
Author(s): Siobhan M. Tobin, Jian-Rui Soh, Hao Su, Andrea Piovano, Anne Stunault, J. Alberto Rodríguez-Velamazán, Yanfeng Guo, and Andrew T. Boothroyd

We report neutron scattering measurements on ${\mathrm{YbMnSb}}_{2}$ which shed light on the nature of the magnetic moments and their interaction with Dirac fermions. Using half-polarized neutron diffraction we measured the field-induced magnetization distribution in the paramagnetic phase and found…

[Phys. Rev. B 107, 195146] Published Tue May 23, 2023

Basal-plane heat transport in graphite thin films
Yangyu Guo, Xiao-Ping Luo, Zhongwei Zhang, Samy Merabia, Masahiro Nomura, and Sebastian Volz
Author(s): Yangyu Guo, Xiao-Ping Luo, Zhongwei Zhang, Samy Merabia, Masahiro Nomura, and Sebastian Volz

While the phonon hydrodynamic regime has recently been highlighted experimentally in graphite films, the understanding and modeling of heat transport along their basal plane remain elusive. From first-principles-based modeling, we predict a significant influence of the surface roughness on basal-pla…

[Phys. Rev. B 107, 195430] Published Tue May 23, 2023

Structural and electronic properties of Tl films on Ag(111): From $(\sqrt{3}×\sqrt{3})$ surface alloy to moiré superstructure
Patrick Härtl, Sven Schemmelmann, Peter Krüger, Markus Donath, and Matthias Bode
Author(s): Patrick Härtl, Sven Schemmelmann, Peter Krüger, Markus Donath, and Matthias Bode

Surface alloys between the heavy metals Bi, Pb, or Sb and noble metals, such as Ag(111), are known for their giant Rashba splitting. Although thallium (Tl) should result in isostructural surface alloys, its structural and electronic properties remained elusive. The authors present here a detailed work on the structural and electronic properties of Tl films epitaxially grown on Ag(111) surfaces. By combining experimental LEED, AES, STM/STS, and IPE with ab initio band structure and charge distribution calculations, the s,pz-derived surface state of the TlAg2 surface alloy is identified, with a weak, but finite, Rashba splitting.

[Phys. Rev. B 107, 205144] Published Tue May 23, 2023

Random magnetic field and the Dirac Fermi surface
Chao-Jung Lee and Michael Mulligan
Author(s): Chao-Jung Lee and Michael Mulligan

We study a single two-dimensional Dirac fermion at finite density, subject to a quenched random magnetic field. At low energies and sufficiently weak disorder, the theory maps onto an infinite collection of 1D chiral fermions (associated to each point on the Fermi surface) coupled by a random vector…

[Phys. Rev. B 107, 205145] Published Tue May 23, 2023

Quantum hydrodynamic model for noble metal nanoplasmonics
Qiang Zhou, Wancong Li, Zi He, Pu Zhang, and Xue-Wen Chen
Author(s): Qiang Zhou, Wancong Li, Zi He, Pu Zhang, and Xue-Wen Chen

The quantum hydrodynamic model (QHDM) has become a versatile and efficient tool for plasmonics at nanometer and even subnanometer length scales, but the theory is principally applicable only to simple metals. For the most common plasmonic materials, i.e., noble metals, QHDM has not been duly justifi…

[Phys. Rev. B 107, 205413] Published Tue May 23, 2023

Quantum pathways of carrier and coherent phonon excitation in bismuth
Azize Koç, Isabel Gonzalez-Vallejo, Matthias Runge, Ahmed Ghalgaoui, Klaus Reimann, Laurenz Kremeyer, Fabian Thiemann, Michael Horn-von Hoegen, Klaus Sokolowski-Tinten, Michael Woerner, and Thomas Elsaesser
Author(s): Azize Koç, Isabel Gonzalez-Vallejo, Matthias Runge, Ahmed Ghalgaoui, Klaus Reimann, Laurenz Kremeyer, Fabian Thiemann, Michael Horn-von Hoegen, Klaus Sokolowski-Tinten, Michael Woerner, and Thomas Elsaesser

Ultrafast mid-infrared excitation of an electron-hole plasma breaks the crystal symmetry of bismuth transiently and opens alternative quantum pathways for the excitation of coherent lattice motions. Probing the transient crystal structure directly by femtosecond x-ray diffraction reveals oscillations of diffracted intensity at a frequency of 2.6 THz, which persist on a picosecond time scale. They reflect coherent wave packet motions along back-folded phonon coordinates in the crystal of reduced symmetry. Optically induced symmetry breaking thus allows for modifying phonon excitations.

[Phys. Rev. B 107, L180303] Published Tue May 23, 2023

Anisotropic optics and gravitational lensing of tilted Weyl fermions
Viktor Könye, Lotte Mertens, Corentin Morice, Dmitry Chernyavsky, Ali G. Moghaddam, Jasper van Wezel, and Jeroen van den Brink
Author(s): Viktor Könye, Lotte Mertens, Corentin Morice, Dmitry Chernyavsky, Ali G. Moghaddam, Jasper van Wezel, and Jeroen van den Brink

We show that tilted Weyl semimetals with a spatially varying tilt of the Weyl cones provide a platform for studying analogs to problems in anisotropic optics as well as curved spacetime. Considering particular tilting profiles, we numerically evaluate the time evolution of electronic wave packets an…

[Phys. Rev. B 107, L201406] Published Tue May 23, 2023

Found 1 papers in prl
Date of feed: Wed, 24 May 2023 03:17:13 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]+)

Ephaptic Coupling as a Resolution to the Paradox of Action Potential Wave Speed and Discordant Alternans Spatial Scales in the Heart
Niels F. Otani, Eileen Figueroa, James Garrison, Michelle Hewson, Laura Muñoz, Flavio H. Fenton, Alain Karma, and Seth H. Weinberg
Author(s): Niels F. Otani, Eileen Figueroa, James Garrison, Michelle Hewson, Laura Muñoz, Flavio H. Fenton, Alain Karma, and Seth H. Weinberg

Previous computer simulations have suggested that existing models of action potential wave propagation in the heart are not consistent with observed wave propagation behavior. Specifically, computer models cannot simultaneously reproduce the rapid wave speeds and small spatial scales of discordant a…

[Phys. Rev. Lett. 130, 218401] Published Tue May 23, 2023

Found 1 papers in prx
Date of feed: Wed, 24 May 2023 03:17:12 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]+)

Performing $\mathrm{SU}(d)$ Operations and Rudimentary Algorithms in a Superconducting Transmon Qudit for $d=3$ and $d=4$
Pei Liu, Ruixia Wang, Jing-Ning Zhang, Yingshan Zhang, Xiaoxia Cai, Huikai Xu, Zhiyuan Li, Jiaxiu Han, Xuegang Li, Guangming Xue, Weiyang Liu, Li You, Yirong Jin, and Haifeng Yu
Author(s): Pei Liu, Ruixia Wang, Jing-Ning Zhang, Yingshan Zhang, Xiaoxia Cai, Huikai Xu, Zhiyuan Li, Jiaxiu Han, Xuegang Li, Guangming Xue, Weiyang Liu, Li You, Yirong Jin, and Haifeng Yu

A multilevel qubit, or “qudit,” in a superconducting transmon shows high fidelity with several rudimentary algorithms, demonstrating the potential of a quantum computing architecture based on up to four levels rather than just two.

[Phys. Rev. X 13, 021028] Published Tue May 23, 2023

Found 1 papers in pr_res
Date of feed: Wed, 24 May 2023 03:17:11 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]+)

Nonreciprocal phonon dichroism induced by Fermi pocket anisotropy in two-dimensional Dirac materials
Wen-Yu Shan
Author(s): Wen-Yu Shan

The origin of nonreciprocal phonon dichroism, that is, the Fermi pocket anisotropy, in magnetic two-dimensional Dirac materials is revealed. Two possible ways to obtain the phonon nonreciprocity are proposed.

[Phys. Rev. Research 5, L022038] Published Tue May 23, 2023

Found 1 papers in nano-lett
Date of feed: Tue, 23 May 2023 20:41:15 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]+)

[ASAP] Abnormal Out-of-Plane Vibrational Raman Mode in Electrochemically Intercalated Multilayer MoS2
Yufei Sun, Shujia Yin, Ruixuan Peng, Jia Liang, Xin Cong, Yi Li, Chenyu Li, Bolun Wang, Miao-Ling Lin, Ping-Heng Tan, Chunlei Wan, and Kai Liu

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Nano Letters
DOI: 10.1021/acs.nanolett.3c01543

Found 1 papers in acs-nano
Date of feed: Wed, 24 May 2023 01:11:06 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]+)

[ASAP] Identification of Ubiquitously Present Polymeric Adlayers on 2D Transition Metal Dichalcogenides
Rita Tilmann, Cian Bartlam, Oliver Hartwig, Bartlomiej Tywoniuk, Nikolas Dominik, Conor P. Cullen, Lisanne Peters, Tanja Stimpel-Lindner, Niall McEvoy, and Georg S. Duesberg

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ACS Nano
DOI: 10.1021/acsnano.3c01649

Found 1 papers in sci-rep

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]+)

Higher-order topological corner state in a reconfigurable breathing kagome lattice consisting of magnetically coupled LC resonators
Hideo Iizuka

Scientific Reports, Published online: 23 May 2023; doi:10.1038/s41598-023-35509-6

Higher-order topological corner state in a reconfigurable breathing kagome lattice consisting of magnetically coupled LC resonators

Found 2 papers in comm-phys

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]+)

Tunable spin and conductance in porphyrin-graphene nanoribbon hybrids
Mads Brandbyge

Communications Physics, Published online: 23 May 2023; doi:10.1038/s42005-023-01231-y

Combining graphene nanoribbons with different functional groups is a flexible way to design new materials with tailored properties suitable for spintronic devices such as chemical sensors. Here, the authors use first-principles calculations to study the quantum transport properties and spin properties of nanoribbon-porphyrin hybrids under the influence of mechanical strain or chemical adsorption.

Geometrical control of topological charge transfer in Shakti-Cairo colloidal ice
Pietro Tierno

Communications Physics, Published online: 23 May 2023; doi:10.1038/s42005-023-01236-7

The topological charge in colloidal ice indicates the particle arrangements at a vertex, or effective spins as in magnetic spin ice but it is not clear how the geometrical constrains of lattices affect these charges. The authors control the location of such charges via geometry transformations, in turn controlling the ice rule in a colloidal ice.