Found 25 papers in cond-mat Non-Hermitian effects have emerged as a new paradigm for the manipulation of
phases of matter that profoundly changes our understanding of non-equilibrium
systems, introducing novel concepts such as exceptional points and spectral
topology, as well as exotic phenomena such as non-Hermitian skin effects
(NHSEs). Most existing studies, however, focus on non-Hermitian eigenstates,
whereas dynamic properties of non-Hermitian systems have been discussed only
very recently, predicting unexpected phenomena such as wave self-healing,
chiral Zener tunneling, and the dynamic NHSEs that are not yet confirmed in
experiments. Here, we report the first experimental observation of rich
non-Hermitian skin dynamics using tunable one-dimensional nonreciprocal
double-chain mechanical systems with glide-time symmetry. Remarkably, dynamic
NHSEs are observed with various dynamic behaviors in different dynamic phases,
revealing the intriguing nature of these phases that can be understood via the
generalized Brillouin zone and the related concepts. Moreover, the observed
tunable non-Hermitian skin dynamics and amplifications, the bulk unidirectional
wave propagation, and the boundary wave trapping provide promising ways to
guide, trap, and amplify waves in a controllable and robust way. Our findings
unveil the fundamental aspects and open a new pathway toward non-Hermitian
dynamics, which will fertilize the study of non-equilibrium phases of matter
and give rise to novel applications in information processing.
By using the Landau-Ginzburg-Wilson paradigm, we show that, near a quantum
critical point (QCP), Cooper pairs at zero temperature would obey a nonlinear
relativistic equation, where the imaginary time emerges as a novel dimension.
This relativistic equation is applicable to certain superconductors at zero
temperature for which the Faber-Pippard coherence length formula holds at and
above the upper critical dimension. Here, we further show that the relativistic
equation leads to a testable prediction in the vicinity of the QCP $T_c=0$,
with $T_c$ being the transition temperature. That is, for 2D overdoped (clean)
superconducting films, when the parameter $T_c/(c_0v_F)$ is lower than a
characteristic scale, the Lorentz symmetry of relativistic equation arouses an
anomalous scaling $\xi_0 \propto T_c^{-1.34}$, where $\xi_0$ denotes the
zero-temperature coherence length, $v_F$ denotes the Fermi velocity, and $c_0$
denotes the Faber-Pippard coefficient. However, when the parameter
$T_c/(c_0v_F)$ is large enough, the Lorentz symmetry may be broken so that the
Faber-Pippard scaling $\xi_0 \propto T_c^{-1}$ is restored.
Two-dimensional shape-morphing networks are common in biological systems and
have garnered attention due to their nontrivial physical properties that
emanate from their cellular nature. Here, we present the fabrication and
characterization of inhomogeneous shape-morphing networks composed of
thermoresponsive microfibers. By strategically positioning fibers with varying
responses, we construct networks that exhibit directional actuation. The
individual segments within the network display either a linear extension or
buckling upon swelling, depending on their radius and length, and the
transition between these morphing behaviors resembles Landau's second-order
phase transition. The microscale variations in morphing behaviors are
translated into observable macroscopic effects, wherein regions undergoing
linear expansion retain their shape upon swelling, whereas buckled regions
demonstrate negative compressibility and shrink. Manipulating the macroscale
morphing by adjusting the properties of the fibrous microsegments offers a
means to modulate and program morphing with mesoscale precision and unlocks
novel opportunities for developing programmable microscale soft robotics and
actuators.
Semiconductor moir\'e superlattices provide a versatile platform to engineer
new quantum solids composed of artificial atoms on moir\'e sites. Previous
studies have mostly focused on the simplest correlated quantum solid - the
Fermi-Hubbard model - where intra-atom interactions are simplified to a single
onsite repulsion energy U. These studies have revealed novel quantum phases
ranging from Mott insulators to quantum anomalous Hall insulators at a filling
of one electron per moir\'e unit cell. New types of quantum solids should arise
at even higher filling factors where the multi-electron configuration of
moir\'e artificial atoms provides new degrees of freedom. Here we report the
experimental observation of Wigner molecular crystals emerging from
multi-electron artificial atoms in twisted bilayer WS2 moir\'e superlattices.
Moir\'e artificial atoms, unlike natural atoms, can host qualitatively
different electron states due to the interplay between quantized energy levels
and Coulomb interactions. Using scanning tunneling microscopy (STM), we
demonstrate that Wigner molecules appear in multi-electron artificial atoms
when Coulomb interactions dominate. Three-electron Wigner molecules, for
example, are seen to exhibit a characteristic trimer pattern. The array of
Wigner molecules observed in a moir\'e superlattice comprises a new crystalline
phase of electrons: the Wigner molecular crystal. We show that these Wigner
molecular crystals are highly tunable through mechanical strain, moir\'e
period, and carrier charge type. Our study presents new opportunities for
exploring quantum phenomena in moir\'e quantum solids composed of
multi-electron artificial atoms.
Van-Hove (vH) singularities in the vicinity of the Fermi level facilitate the
emergence of electronically mediated Fermi surface instabilities. This is
because they provide a momentum-localized enhancement of density of states
enhancing selective electronic scattering channels. High-temperature
topological superconductivity has been argued for in graphene at vH filling
which, however, has so far proven inaccessible due to the demanded large doping
from pristine half filling. We propose compensated metallicity as a path to
unlock vH-driven pairing close to half filling in an electronic honeycomb
lattice model. It is enabled through the strong breaking of chiral symmetry
from intra-sublattice hybridization, leading to the emergence of a hole pocket
(hp) nearby the van-Hove points $M$ at the Brillouin zone boundary and an
electron pocket (ep) around the zone center $\Gamma$. While the ep is radially
symmetric and barely contributing to the electronic ordering selection, the hp
is dominated by its vH signature and yields electronic order at elevated
scales.
We derive the electromagnetic response of a particular fermionic sector in
the minimal QED contribution to the Standard Model Extension (SME), which can
be physically realized in terms of a model describing a tilted and anisotropic
Weyl semimetal (WSM). The contact is made through the identification of the
Dirac-like Hamiltonian resulting from the SME with that corresponding to the
WSM in the linearized tight-binding approximation. We first calculate the
effective action by computing the non-perturbative vacuum polarization tensor
using thermal field theory techniques, focusing upon the corrections at finite
chemical potential and zero temperature. Next, we confirm our results by a
direct calculation of the anomalous Hall current within a chiral kinetic theory
approach.
In an ideal Dirac cone picture of the WSM (isotropic and non-tilted) such
response is known to be governed by axion electrodynamics, with the space-time
dependent axion angle $\Theta (\mathbf{r},t) = 2 (\mathbf{b} \cdot \mathbf{r} -
b _{0} t)$, being $2 \mathbf{b}$ and $2b _{0}$ the separation of the Weyl nodes
in momentum and energy, respectively. In this paper we demonstrate that the
node tilting and the anisotropies induce novel corrections at a finite density
which however preserve the structure of the axionic field theory. We apply our
results to the ideal Weyl semimetal $\mathrm{EuCd}_{2}\mathrm{As}_{2}$ and to
the highly anisotropic and tilted monopnictide $\mathrm{TaAs}$.
In this work, we study the near-field radiative energy, linear-momentum, and
angular-momentum transfer from a current-biased graphene to nanoparticles. The
electric current through the graphene sheet induces nonequilibrium
fluctuations, causing energy and momentum transfer even in the absence of a
temperature difference. The inherent spin-momentum locking of graphene surface
plasmon polaritons leads to an in-plane torque perpendicular to the electric
current. In the presence of a temperature difference, energy transfer is
greatly enhanced while the lateral force and torque remains within the same
order. Our work explores the potential of utilizing current-biased graphene to
manipulate nanoparticles.
The realization of topological states of matter in ultracold atomic gases is
currently the subject of intense experimental activity. Using a synthetic
dimension, encoded in a non-spatial degree of freedom, can greatly simplify the
simulation of gauge fields and give access to exotic topological states. We
review here recent advances in the field and discuss future perspectives for
interacting systems.
The electronic tunneling properties of trilayer graphene (TLG) are
significantly influenced by the specific stacking order. To illustrate this
stacking influence, we investigate the transport properties of a p-n-p junction
formed with ABC-ABA-ABC stacking TLG. Utilizing the transfer matrix method and
considering continuity conditions at the junction boundaries, we establish
transmission, reflection probabilities, and conductance. Remarkably, electron
transport through the ABC-ABA-ABC junction demonstrates Klein tunneling,
resulting in high conductance even in the absence of a potential barrier $V_0$.
This phenomenon is attributed to the effective barrier induced by our stacking,
facilitating the passage of a maximum number of electrons. However, the
presence of $V_0$ diminishes Klein tunneling, leading to conductance minima.
Furthermore, we reveal that the interlayer bias $\delta$ causes hybridization
of the linear and parabolic bands of ABA-TLG in the junction, reducing
resonances. In cases where $\delta\neq0$ and $V_0\neq0$, a suppression of the
gap is observed, contrary to the results obtained in ABC tunneling studies
where a gap exists.
Solutions of long, flexible polymer molecules are complex fluids that
simultaneously exhibit fluid-like and solid-like behaviour. When subjected to
an external flow, dilute polymer solutions exhibit elastic turbulence - a
unique, chaotic flow state absent in Newtonian fluids, like water. Unlike its
Newtonian counterpart, elastic turbulence is caused by polymer molecules
stretching and aligning in the flow, and can occur at vanishing inertia. While
experimental realisations of elastic turbulence are well-documented, there is
currently no understanding of its mechanism. Here, we present large-scale
direct numerical simulations of elastic turbulence in pressure-driven flows
through straight channels. We demonstrate that the transition to elastic
turbulence is sub-critical, giving rise to spot-like flow structures that,
further away from the transition, eventually spread throughout the domain. We
provide evidence that elastic turbulence is organised around unstable coherent
states that are localised close to the channel midplane.
In the calculations of lattice thermal conductivity ($\kappa_{\text{L}}$),
vital contributions stemming from four-phonon scattering are often neglected.
The significance of four-phonon scattering in the thermal transport properties
of monolayer (ML) MoS$_{2}$ has been unraveled using first-principles
calculations combined with the Boltzmann transport equation. If only
three-phonon scattering processes are considered then the $\kappa_{\text{L}}$
is found to be significantly overestimated ($\sim$ 115.8 Wm$^{-1}$K$^{-1}$ at
300 K). With the incorporation of the four-phonon scattering processes, the
$\kappa_{\text{L}}$ reduces to 24.6 Wm$^{-1}$K$^{-1}$, which is found to be
closer to the experimentally measured $\kappa_{\text{L}}$ of 34.5
Wm$^{-1}$K$^{-1}$. Four-phonon scattering significantly impacts the carrier
lifetime ($\tau$) of the low-energy out-of-plane acoustic mode (ZA) phonons and
thereby, suppresses its contribution in $\kappa_{\text{L}}$ from 64% (for
three-phonon scattering) to 16% (for both three- and four-phonon scatterings).
The unusually high four-phonon scattering rate ($\tau_{4}^{-1}$) of the ZA
phonons is found to result from the simultaneous effect of the acoustic-optical
frequency gap, strong anharmonicity, and the reflection symmetry imposed
selection rule. The strong coupling between the quadratic dispersion of the ZA
mode and the $\tau_{4}^{-1}$ is discovered by the application of mechanical
strain. The strain induced increase in the linearity of the ZA mode dispersion
dramatically reduces the significance of the four-phonon scattering in the
strained ML-MoS$_{2}$, both qualitatively and quantitatively. These conclusions
will provide significant insights into the thermal transport phenomena in
ML-MoS$_{2}$, as well as any other 2D material.
The interface between a metal electrode and an organic semiconductor (OS)
layer has a defining role in the properties of the resulting device. To obtain
a desired performance, interlayers are introduced to modify the adhesion and
growth of OS and enhance the efficiency of charge transport through the
interface. However, the employed interlayers face common challenges, including
a lack of electric dipoles to tune the mutual position of energy levels, being
too thick for efficient electronic transport, or being prone to intermixing
with subsequently deposited OS layers. Here, we show that monolayers of
1,3,5-tris(4 carboxyphenyl)benzene (BTB) with fully deprotonated carboxyl group
on silver substrates form a compact layer resistant to intermixing while
mediating energy level alignment and showing a large insensitivity to substrate
termination. Employing a combination of surface-sensitive techniques, i.e.,
low-energy electron microscopy and diffraction, X-ray photoelectron
spectroscopy, and scanning tunneling microscopy, we have comprehensively
characterized the compact layer and proven its robustness against mixing with
the subsequently deposited organic semiconductor layer. DFT calculations show
that the robustness arises from a strong interaction of carboxylate groups with
the Ag surface, and thus, the BTB in the first layer is energetically favored.
Synchrotron radiation photoelectron spectroscopy shows that this layer displays
considerable electrical dipoles that can be utilized for work function
engineering and electronic alignment of molecular frontier orbitals with
respect to the substrate Fermi level. Our work thus provides a widely
applicable molecular interlayer and general insights necessary for engineering
of charge injection layers for efficient organic electronics.
We study the linear response of relativistic superfluids with a non-zero
superfluid velocity. For sufficiently large superflow, an instability develops
via the crossing of a pole of the retarded Green's functions to the upper half
complex frequency plane. We show that this is caused by a local thermodynamic
instability, i.e. when an eigenvalue of the static susceptibility matrix (the
second derivatives of the free energy) diverges and changes sign. The onset of
the instability occurs when $\partial_{\zeta}(n_s\zeta)=0$, with $\zeta$ the
norm of the superfluid velocity and $n_s$ the superfluid density. The Landau
instability for non-relativistic superfluids such as Helium 4 also coincides
with the non-relativistic version of this criterion. We then turn to
gauge/gravity duality and show that this thermodynamic instability criterion
applies equally well to strongly-coupled superfluids. In passing, we compute
holographically a number of transport coefficients parametrizing deviations
out-of-equilibrium in the hydrodynamic regime and demonstrate that the gapless
quasinormal modes of the dual planar black hole match those predicted by
superfluid hydrodynamics.
The topological R\'enyi and entanglement entropies depend on the bipartition
of the manifold and the choice of the ground states. However, these
entanglement quantities remain invariant under a coordinate transformation when
the bipartition also undergoes the same transformation. In the context of
topological quantum field theories, these coordinate transformations reduce to
representations of the mapping class group on the manifold of the Hilbert
space. We employ this invariant property of the R\'enyi and entanglement
entropies under coordinate transformations for TQFTs in (2 + 1) dimensions on a
torus with various bipartitions. By utilizing the replica trick and the surgery
method to compute the topological R\'enyi and entanglement entropies, the
invariant property results in Verlinde-like formulas. Furthermore, for the
bipartition with interfaces as two non-intersecting torus knots, an $SL(2,
\mathbb{Z})$ transformation can untwist the torus knots, leading to a simple
bipartition with an effective ground state. This invariant property allows us
to demonstrate that the topological entanglement entropy has a lower bound $-2
\ln D$, where $D$ is the total quantum dimensions of the system.
In a broad class of sparse random constraint satisfaction problems(CSP), deep
heuristics from statistical physics predict that there is a condensation phase
transition before the satisfiability threshold, governed by one-step replica
symmetry breaking(1RSB). In fact, in random regular k-NAE-SAT, which is one of
such random CSPs, it was verified \cite{ssz22} that its free energy is
well-defined and the explicit value follows the 1RSB prediction. However, for
any model of sparse random CSP, it has been unknown whether the solution space
indeed condenses on O(1) clusters according to the 1RSB prediction. In this
paper, we give an affirmative answer to this question for the random regular
k-NAE-SAT model. Namely, we prove that with probability bounded away from zero,
most of the solutions lie inside a bounded number of solution clusters whose
sizes are comparable to the scale of the free energy. Furthermore, we establish
that the overlap between two independently drawn solutions concentrates
precisely at two values. Our proof is based on a detailed moment analysis of a
spin system, which has an infinite spin space that encodes the structure of
solution clusters. We believe that our method is applicable to a broad range of
random CSPs in the 1RSB universality class.
The pair correlation function (PCF) has proven an effective tool for
analyzing many physical systems due to its simplicity and its applicability to
simulated and experimental data. However, as an averaged quantity, the PCF can
fail to capture subtle structural differences in particle arrangements, even
when those differences can have a major impact on system properties. Here, we
use Voronoi topology to introduce a discrete version of the PCF that highlights
local inter-particle topological configurations. The advantages of the Voronoi
PCF are demonstrated in several examples including crystalline, hyperuniform,
and active systems showing clustering and giant number fluctuations.
We explore computationally tractable deformations of the SYK model. The
deformed theories are described by the sum of two SYK Hamiltonians with
differing numbers, $q$ and $\tilde{q}$, of interacting fermions. In the large
$N$ limit, employing analytic and numerical tools, we compute finite
temperature correlation functions and thermodynamic quantities. We identify a
novel analytically solvable model in the large $q$ limit. We find that, under
certain circumstances, the thermal RG flow in the strongly coupled infrared
phase exhibits two regions of linear-in-temperature entropy, which we interpret
in terms of Schwarzian actions. Using conformal perturbation theory we compute
the leading relevant correction away from the intermediate near-conformal fixed
point. Holographic spacetimes in two spacetime dimensions that reproduce the
thermodynamics of the microphysical theory are discussed. These are flow
geometries that interpolate between two Euclidean near-AdS$_2$ spacetimes with
different radii. The Schwarzian soft mode corresponding to the AdS$_2$ region
in the deep interior resides entirely within the geometric regime.
We study mesoscopic signatures of the topological Anderson transitions in
topological disordered chains. To this end we introduce an integer-valued
sample-specific definition of the topological index in finite size systems. Its
phase diagram exhibits a fascinating structure of intermittent topological
phases, dubbed topological islands. Their existence is rooted in the real zeros
of the underlying random polynomial. Their statistics exhibits finite-size
scaling, pointing to the location of the bulk topological Anderson transition.
While the average theories in AIII and BDI symmetry classes are rather similar,
the corresponding patterns of topological islands and their statistics are
qualitatively different. We also discuss observable signatures of sharp
topological transitions in mesoscopic systems, such as persistent currents and
entanglement spectra.
We study a 4-orbital tight-binding (TB) model for ZrSiS from the square
sublattice generated by the Si atoms. After studying three other alternatives,
we endow such model with a new effective spin-orbit coupling (SOC) consistent
with {\em ab initio} dispersions around the Fermi energy ($E_F$) in four
systematic steps: (1) We calculate the electronic dispersion of bulk ZrSiS
using an implementation of density-functional theory (DFT) based on numeric
atomic orbitals [{\em J. Phys.: Condens. Matter} {\bf 14}, 2745 (2002)] in
which on-site and off-site SOC can be told apart. As a result, we determine
that local SOC-induced band gaps around $E_F$ are predominantly created by the
on-site contribution. (2) Gradually reducing the atomic basis set size, we then
create an electronic band structure with 16 orbitals per unit cell (u.c.) which
retains the qualitative features of the dispersion around $E_F$, including
SOC-induced band gaps. (3) Zr is the heaviest element on this compound and it
has a non-negligible contribution to the electronic dispersion around $E_F$; we
show that it provides the strongest contribution to the SOC-induced band gap.
(4) Using L\"{o}wdin partitioning approach, we project the effect of SOC onto
the 4-orbital Hamiltonian. This way, we facilitate an effective SOC interaction
that was explicitly informed by {\em ab initio} input.
Recent experiments on Bernal bilayer graphene (BLG) deposited on monolayer
WSe$_2$ revealed robust, ultra-clean superconductivity coexisting with sizable
induced spin-orbit coupling. Here we propose BLG/WSe$_2$ as a platform to
engineer gate-defined planar topological Josephson junctions, where the normal
and superconducting regions descend from a common material. More precisely, we
show that if superconductivity in BLG/WSe$_2$ is gapped and emerges from a
parent state with inter-valley coherence, then Majorana zero modes can form in
the barrier region upon applying weak in-plane magnetic fields. Our results
spotlight a potential pathway for `internally engineered' topological
superconductivity that minimizes detrimental disorder and
orbital-magnetic-field effects.
We introduce a message-passing-neural-network-based wave function Ansatz to
simulate extended, strongly interacting fermions in continuous space. Symmetry
constraints, such as continuous translation symmetries, can be readily embedded
in the model. We demonstrate its accuracy by simulating the ground state of the
homogeneous electron gas in three spatial dimensions at different densities and
system sizes. With orders of magnitude fewer parameters than state-of-the-art
neural-network wave functions, we demonstrate better or comparable ground-state
energies. Reducing the parameter complexity allows scaling to $N=128$
electrons, previously inaccessible to neural-network wave functions in
continuous space, enabling future work on finite-size extrapolations to the
thermodynamic limit. We also show the Ansatz's capability of quantitatively
representing different phases of matter.
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.
Kagome materials provide a promising platform to explore intriguing
correlated phenomena including magnetism, charge density wave (CDW), and
nontrivial band topology. Recently, a CDW order was observed in
antiferromagnetic kagome metal FeGe, sparking enormous research interests in
intertwining physics of CDW and magnetism. Two of the core questions are (i)
what are the driving forces of the CDW transition in FeGe and (ii) whether
magnetism play a critical role in the transition. Such questions are critical
as conventional mechanisms of van Hove singularities and Fermi surface nesting
fail to explain the stable pristine phase, as well as the role of magnetism.
Here, supported by density functional theory and tight-binding models, we
unravel the triple-well CDW energy landscape of FeGe, indicating that both the
pristine and CDW phases are locally stable. We point out that an entire
downward shift of Ge band, instead of the previously proposed Fe bands,
competes with the lattice distortion energy, driving the triple-well CDW
transition. It is indeed a cooperation between the Peierls-like effect and the
Fermi energy pinning phenomenon, which is distinct from the conventional
Peierls effect that drives a double-well transition. Moreover, we demonstrate
that the antiferromagnetic order also plays a critical role in driving the CDW
transition, through weakening the Fe-Ge hybridization by exchange splitting and
lowering the position of Ge-bands with respect to the Fermi energy. Our work
thus not only deepens the understanding of the CDW mechanism in FeGe, but also
indicates an intertwined connection between the emergent magnetism and CDW in
kagome materials.
In graphene on transition metal dichalcogenides, proximity-induced Rashba and
spin-valley Zeeman SOCs can coexist that modify graphene's electronic band
differently. Here, we show that the Landau levels (LLs) are also affected by
these SOCs distinctively enough to estimate their relative strengths from the
Landau fan diagram. Using a simple theoretical model, we calculated the LL
spectrums of graphene for different SOC strengths, and found that when the
total SOC is strong enough (i.e., when it is comparable to the half of the
energy gap between the LLs of an intrinsic graphene), the corresponding LLs
will split and cross with others depending sensitively on the relative
strengths of the SOC terms. To demonstrate how one can use it to estimate the
relative SOC strengths, we first identified the four key features that are well
separated from the complex background and can be compared with experiment
directly, and used them to show that in our sample, the Rashba SOC is stronger
than the spin-valley Zeeman SOC that is consistent with other spectroscopic
measurements. Our study therefore provides a simple and practical strategy to
analyze the LL spectrum in graphene with SOC before carrying out more in-depth
measurements.
Active nematics are dense systems of rodlike particles that consume energy to
drive motion at the level of the individual particles. They exist in natural
systems like biological tissues and artificial materials such as suspensions of
self-propelled colloidal particles or synthetic microswimmers. Active nematics
have attracted significant attention in recent years due to their spectacular
nonequilibrium collective spatiotemporal dynamics, which may enable
applications in fields such as robotics, drug delivery, and materials science.
The director field, which measures the direction and degree of alignment of the
local nematic orientation, is a crucial characteristic of active nematic and is
essential for studying topological defects. However, determining the director
field is a significant challenge in many experimental systems. Although
director fields can be derived from images of active nematics using traditional
imaging processing methods, the accuracy of such methods are highly sensitive
to the settings of the algorithms. These settings must be tuned from
image-to-image due to experimental noise, intrinsic noise of the imaging
technology, and perturbations caused by changes in experimental conditions.
This sensitivity currently limits automatic analysis of active nematics. To
address this, we developed a machine learning model for extracting reliable
director fields from raw experimental images, which enables accurate analysis
of topological defects. Application of the algorithm to experimental data
demonstrates that the approach is robust and highly generalizable to
experimental settings that are different from those in the training data. It
could be a promising tool for investigating active nematics and may be
generalized to other active matter systems.

Date of feed: Thu, 14 Dec 2023 01:30:00 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) **Observation of dynamic non-Hermitian skin effects. (arXiv:2312.07564v1 [quant-ph])**

Zhen Li, Li-Wei Wang, Xulong Wang, Zhi-Kang Lin, Guancong Ma, Jian-Hua Jiang

**Superconducting quantum criticality and the anomalous scaling: A nonlinear relativistic equation. (arXiv:2312.07567v1 [cond-mat.supr-con])**

Yong Tao

**From Microscale Variations to Macroscopic Effects: Directional Actuation, Phase Transition, and Negative Compressibility in Microfiber-Based Shape-Morphing Networks. (arXiv:2312.07568v1 [cond-mat.soft])**

Shiran Ziv Sharabani, Elad Livnat, Maia Abuchalja, Noa Haphiloni, Nicole Edelstein-Pardo, Tomer Reuveni, Maya Molco, Amit Sitt

**Wigner Molecular Crystals from Multi-electron Moir\'e Artificial Atoms. (arXiv:2312.07607v1 [cond-mat.mes-hall])**

Hongyuan Li, Ziyu Xiang, Aidan P. Reddy, Trithep Devakul, Renee Sailus, Rounak Banerjee, Takashi Taniguchi, Kenji Watanabe, Sefaattin Tongay, Alex Zettl, Liang Fu, Michael F. Crommie, Feng Wang

**Van-Hove tuning of Fermi surface instabilities through compensated metallicity. (arXiv:2312.07653v1 [cond-mat.str-el])**

Hendrik Hohmann, Matteo Dürrnagel, Matthew Bunney, Tilman Schwemmer, Titus Neupert, Stephan Rachel, Ronny Thomale

**Lorentz invariance violation and the CPT-odd electromagnetic response of a tilted anisotropic Weyl semimetal. (arXiv:2312.07791v1 [hep-th])**

Andrés Gómez, R. Martínez von Dossow, A. Martín-Ruiz, Luis F. Urrutia

**Current-induced near-field radiative energy, linear-momentum, and angular-momentum transfer. (arXiv:2312.07954v1 [physics.optics])**

Huimin Zhu, Gaomin Tang, Lei Zhang, Jun Chen

**Atomic topological quantum matter using synthetic dimensions. (arXiv:2312.07984v1 [cond-mat.quant-gas])**

Aurélien Fabre, Sylvain Nascimbene

**Tunneling through ABC-ABA-ABC trilayer graphene junction. (arXiv:2312.08046v1 [cond-mat.mes-hall])**

Abderrahim El Mouhafid, Mouhamadou Hassane Saley, Ahmed Jellal

**Purely elastic turbulence in pressure-driven channel flows. (arXiv:2312.08091v1 [physics.flu-dyn])**

Martin Lellep, Moritz Linkmann, Alexander Morozov

**Understanding the Role of Four-Phonon Scattering in the Lattice Thermal Transport of Monolayer MoS$_{2}$. (arXiv:2312.08219v1 [cond-mat.mtrl-sci])**

Saumen Chaudhuri, Amrita Bhattacharya, A. K. Das, G. P. Das, B. N. Dev

**Robust Dipolar Layers between Organic Semiconductors and Silver for Energy-Level Alignment. (arXiv:2312.08233v1 [cond-mat.mtrl-sci])**

Tomáš Krajňák, Veronika Stará, Pavel Procházka, Jakub Planer, Tomáš Skála, Matthias Blatnik, Jan Čechal

**Hydrodynamics and instabilities of relativistic superfluids at finite superflow. (arXiv:2312.08243v1 [hep-th])**

Daniel Areán, Blaise Goutéraux, Eric Mefford, Filippo Sottovia

**Topological entanglement entropy for torus knot bipartitions and the Verlinde-like formulas. (arXiv:2312.08348v1 [cond-mat.str-el])**

Chih-Yu Lo, Po-Yao Chang

**One-step replica symmetry breaking of random regular NAE-SAT I. (arXiv:2011.14270v3 [math.PR] UPDATED)**

Danny Nam, Allan Sly, Youngtak Sohn

**Pair correlation function based on Voronoi topology. (arXiv:2210.09731v2 [cond-mat.dis-nn] UPDATED)**

Vasco M. Worlitzer, Gil Ariel, Emanuel A. Lazar

**Renormalisation Group Flows of Deformed SYK Models. (arXiv:2212.04944v2 [hep-th] UPDATED)**

Dionysios Anninos, Damián A. Galante, Sameer U. Sheorey

**Anatomy of topological Anderson transitions. (arXiv:2301.04565v2 [cond-mat.dis-nn] UPDATED)**

Hao Zhang, Alex Kamenev

**Tight-binding model with sublattice-asymmetric spin-orbit coupling for square-net nodal line Dirac semimetals. (arXiv:2304.03438v3 [cond-mat.mtrl-sci] UPDATED)**

Gustavo S. Orozco-Galvan, Amador Garcia-Fuente, Salvador Barraza-Lopez

**Gate-Defined Topological Josephson Junctions in Bernal Bilayer Graphene. (arXiv:2304.11807v3 [cond-mat.mes-hall] UPDATED)**

Ying-Ming Xie, Étienne Lantagne-Hurtubise, Andrea F. Young, Stevan Nadj-Perge, Jason Alicea

**Message-Passing Neural Quantum States for the Homogeneous Electron Gas. (arXiv:2305.07240v3 [quant-ph] UPDATED)**

Gabriel Pescia, Jannes Nys, Jane Kim, Alessandro Lovato, Giuseppe Carleo

**Majorana zero modes in gate-defined germanium hole nanowires. (arXiv:2305.14313v2 [cond-mat.mes-hall] UPDATED)**

Katharina Laubscher, Jay D. Sau, Sankar Das Sarma

**Triple-Well Charge Density Wave Transition Driven by Cooperation between Peierls-like Effect and Antiferromagnetic Order in FeGe. (arXiv:2307.10565v2 [cond-mat.mtrl-sci] UPDATED)**

Binhua Zhang, Junyi Ji, Changsong Xu, Hongjun Xiang

**Landau-level spectrum and the effect of spin-orbit coupling in monolayer graphene on transition metal dichalcogenides. (arXiv:2310.00686v2 [cond-mat.mes-hall] UPDATED)**

Qing Rao, Hongxia Xue, Dong-Keun Ki

**A Machine Learning Approach to Robustly Determine Director Fields and Analyze Defects in Active Nematics. (arXiv:2310.12449v2 [cond-mat.soft] UPDATED)**

Yunrui Li, Zahra Zarei, Phu N. Tran, Yifei Wang, Aparna Baskaran, Seth Fraden, Michael F. Hagan, Pengyu Hong

Found 6 papers in prb Tellurium (Te) is one of the $p$-orbital chalcogens, which shows attractive physical properties at ambient pressure. Here, we systematically investigate both structural and electronic evolution of Te single crystal under high pressure up to 40 GPa. The pressure dependence of the experimental Raman s… We calculate the zero-temperature dc electrical conductivity in the collisionless $ℏω/{k}_{B}T→∞$ limit at superconductor-insulator transitions in the $(2+1)\mathrm{d}$ XY model universality class. We use a dual model consisting of a single Dirac fermion at zero density, coupled to a Chern-Simons ga… A topological phase can be engineered in quantum physics from the Bloch sphere of a spin-1/2 showing a hedgehog structure as a result of a radial magnetic field. We elaborate on a relation between the formation of an entangled wavefunction at one pole, in a two-spins model, and an interesting pair o… The chiral edge modes of a topological superconductor can transport fermionic quasiparticles with Abelian exchange statistics, but they can also transport non-Abelian anyons: edge vortices bound to a $π$-phase domain wall that propagates along the boundary. A pair of such edge vortices is injected b… In an infinite twisted bilayer graphene lattice, flat bands emerge, representing electrons localized at the AA stacking regions. This study investigates the behavior of these bands when dealing with incomplete moiré supercells in twisted bilayer graphene nanoribbons. The findings reveal a transition from dispersive to flat bands near charge neutrality as the supercell completeness varies. Moreover, it is observed that the microscopic edges can influence the energy of states localized at the AA regions near the borders. Recent theoretical works on two-dimensional molybdenum disulfide (${\mathrm{MoS}}_{2}$) with sulfur vacancies predict that the suppression of thermal transport in ${\mathrm{MoS}}_{2}$ by point defects is more prominent in monolayers and becomes negligible as the layer number increases. Here, we inve…

Date of feed: Thu, 14 Dec 2023 04:16:59 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) **Superconductivity and critical fields of tellurium single crystal under high pressure**

Lingxiao Zhao, Cuiying Pei, Juefei Wu, Yi Zhao, Qi Wang, Bangshuai Zhu, Changhua Li, Weizheng Cao, and Yanpeng Qi

Author(s): Lingxiao Zhao, Cuiying Pei, Juefei Wu, Yi Zhao, Qi Wang, Bangshuai Zhu, Changhua Li, Weizheng Cao, and Yanpeng Qi

[Phys. Rev. B 108, 214518] Published Wed Dec 13, 2023

**Universal conductivity at a two-dimensional superconductor-insulator transition: The effects of quenched disorder and Coulomb interaction**

Chao-Jung Lee and Michael Mulligan

Author(s): Chao-Jung Lee and Michael Mulligan

[Phys. Rev. B 108, 235142] Published Wed Dec 13, 2023

**One-half topological number in entangled quantum physics**

Karyn Le Hur

Author(s): Karyn Le Hur

[Phys. Rev. B 108, 235144] Published Wed Dec 13, 2023

**Dynamical simulation of the injection of vortices into a Majorana edge mode**

I. M. Flór, A. Donís-Vela, C. W. J. Beenakker, and G. Lemut

Author(s): I. M. Flór, A. Donís-Vela, C. W. J. Beenakker, and G. Lemut

[Phys. Rev. B 108, 235309] Published Wed Dec 13, 2023

**Flat bands and electronic localization in twisted bilayer graphene nanoribbons**

Elias Andrade, Pierre A. Pantaleón, Francisco Guinea, and Gerardo G. Naumis

Author(s): Elias Andrade, Pierre A. Pantaleón, Francisco Guinea, and Gerardo G. Naumis

[Phys. Rev. B 108, 235418] Published Wed Dec 13, 2023

**Layer number and stacking order dependent thermal transport in molybdenum disulfide with sulfur vacancies**

Ranjuna M K and Jayakumar Balakrishnan

Author(s): Ranjuna M K and Jayakumar Balakrishnan

[Phys. Rev. B 108, 245411] Published Wed Dec 13, 2023

Found 1 papers in prl The development of patterned multiquantum well heterostructures in GaAs/AlGaAs waveguides has recently made it possible to achieve exciton-polariton condensation in a topologically protected bound state in the continuum (BIC). Polariton condensation was shown to occur above a saddle point of the two…

Date of feed: Thu, 14 Dec 2023 04:16:57 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99) **Polariton Condensation in Gap-Confined States of Photonic Crystal Waveguides**

F. Riminucci, A. Gianfrate, D. Nigro, V. Ardizzone, S. Dhuey, L. Francaviglia, K. Baldwin, L. N. Pfeiffer, D. Ballarini, D. Trypogeorgos, A. Schwartzberg, D. Gerace, and D. Sanvitto

Author(s): F. Riminucci, A. Gianfrate, D. Nigro, V. Ardizzone, S. Dhuey, L. Francaviglia, K. Baldwin, L. N. Pfeiffer, D. Ballarini, D. Trypogeorgos, A. Schwartzberg, D. Gerace, and D. Sanvitto

[Phys. Rev. Lett. 131, 246901] Published Wed Dec 13, 2023

Found 1 papers in prx The fundamental model for understanding Mott insulators is the single-band Hubbard model. An ideal realization of that model arises in Nb${}_{3}$Cl${}_{8}$, proving a powerful system for exploring Mott physics and other correlated states.

Date of feed: Thu, 14 Dec 2023 04:16:57 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99) **Discovery of a Single-Band Mott Insulator in a van der Waals Flat-Band Compound**

Shunye Gao *et al.*

Author(s): Shunye Gao *et al.*

[Phys. Rev. X 13, 041049] Published Wed Dec 13, 2023

Found 1 papers in nano-lett

Date of feed: Wed, 13 Dec 2023 22:03:49 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99) **[ASAP] Excitonic Effects in Energy-Loss Spectra of Freestanding Graphene**

Alberto Guandalini, Ryosuke Senga, Yung-Chang Lin, Kazu Suenaga, Andrea Ferretti, Daniele Varsano, Andrea Recchia, Paolo Barone, Francesco Mauri, Thomas Pichler, and Christian KrambergerNano LettersDOI: 10.1021/acs.nanolett.3c03863

Found 1 papers in acs-nano

Date of feed: Wed, 13 Dec 2023 23:04:28 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99) **[ASAP] Spatiotemporal Observation of Quasi-Ballistic Transport of Electrons in Graphene**

Ryan J. Scott, Pavel Valencia-Acuna, and Hui ZhaoACS NanoDOI: 10.1021/acsnano.3c08816

Found 2 papers in science-adv

Date of feed: Wed, 13 Dec 2023 20:00:18 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) **Plasma membrane nanodeformations promote actin polymerization through CIP4/CDC42 recruitment and regulate type II IFN signaling**

Benjamin Ledoux, Natacha Zanin, Jinsung Yang, Vincent Mercier, Charlotte Coster, Christine Dupont-Gillain, David Alsteens, Pierre Morsomme, Henri-François Renard

Science Advances, Volume 9, Issue 50, December 2023.

**Thermally generated spin current in the topological insulator Bi2Se3**

Rakshit Jain, Max Stanley, Arnab Bose, Anthony R. Richardella, Xiyue S. Zhang, Timothy Pillsbury, David A. Muller, Nitin Samarth, Daniel C. Ralph

Science Advances, Volume 9, Issue 50, December 2023.

Found 1 papers in scipost **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) **$T \overline{T}$-Like Flows and $3d$ Nonlinear Supersymmetry, by Christian Ferko, Yangrui Hu, Zejun Huang, Konstantinos Koutrolikos, Gabriele Tartaglino-Mazzucchelli**

< author missing >

Submitted on 2023-12-14, refereeing deadline 2024-01-19.