Found 38 papers in cond-mat Non-Hermitian skin effect (NHSE), characterized by a majority of eigenstates
localized at open boundaries, is one of the most iconic phenomena in
non-Hermitian lattices. Despite notable experimental studies implemented, most
of them witness only certain signs of the NHSE rather than the intrinsic
exponential localization inherent in eigenstates, owing to the ubiquitous and
inevitable background loss. Even worse, the experimental observation of the
NHSE would be completely obscured in highly lossy cases. Here, we theoretically
propose a dual test approach to eliminate the destructive loss effect and track
the intrinsic NHSE that is essentially irrelevant to background loss.
Experimentally, the effectiveness of this approach is precisely validated by
one- and two-dimensional non-Hermitian acoustic lattices. Our study sheds new
light on the previously untapped intrinsic aspect of the NHSE, which is of
particular significance in non-Hermitian topological physics.
Quantum geometry defines the phase and amplitude distances between quantum
states. The phase distance is characterized by the Berry curvature and thus
relates to topological phenomena. The significance of the full quantum
geometry, including the amplitude distance characterized by the quantum metric,
has started to receive attention in the last few years. Various quantum
transport and interaction phenomena have been found to be critically influenced
by quantum geometry. For example, quantum geometry allows counterintuitive flow
of supercurrent in a flat band where single electrons are immobile. In this
Essay, I will discuss my view of the important open problems and future
applications of this research topic and will try to inspire the reader to come
up with further ideas. At its best, quantum geometry can open a new chapter in
band theory and lead to breakthroughs as transformative as room-temperature
superconductivity. However, first, more experiments directly showing the effect
of quantum geometry are needed. We also have to integrate quantum geometry
analysis in our most advanced numerical methods. Further, the ramifications of
quantum geometry should be studied in a wider range, including electric and
electromagnetic responses and interaction phenomena in free- and
correlated-electron materials, bosonic systems, optics, and other fields.
Full-shell nanowires have been proposed as an alternative nanowire design in
the search of topological superconductivity and Majorana zero modes (MZMs).
They are hybrid nanostructures consisting of a semiconductor core fully covered
by a thin superconductor shell and subject to a magnetic flux. In this work we
critically examine this proposal, finding a very rich spectral phenomenology
that combines the Little-Parks modulation of the parent-gap superconductor with
flux, the presence of flux-dispersing Caroli-de Gennes-Matricon (CdGM) analog
subgap states, and the emergence of MZMs across finite flux intervals that
depend on the transverse wavefunction profile of the charge density in the core
section. Through microscopic simulations and analytical derivations, we study
different regimes for the semiconductor core, ranging from the hollow-core
approximation, to the tubular-core nanowire appropriate for a semiconductor
tube with an insulating core, to the solid-core nanowire. We compute the phase
diagrams for the different models in cylindrical nanowires and find that MZMs
typically coexist with CdGM analogs at zero energy, rendering them gapless.
However, we also find topologically protected parameter regions, or islands,
with gapped MZMs. In this sense, the most promising candidate to obtain
topologically protected MZMs in a full-shell geometry is the nanowire with a
tubular-shaped core. Moving beyond pristine nanowires, we study the effect of
mode mixing perturbations. Strikingly, mode mixing can act like a topological
$p$-wave pairing between particle-hole Bogoliubov partners, and is therefore
able to create new topologically protected MZMs in regions of the phase diagram
that were originally trivial. As a result, the phase diagram is utterly
transformed and exhibits protected MZMs in around half of the parameter space.
The understanding of phenomena falling outside the Ginzburg-Landau paradigm
of phase transitions represents a key challenge in condensed matter physics. A
famous class of examples is constituted by the putative deconfined quantum
critical points between two symmetry-broken phases in layered quantum magnets,
such as pressurised SrCu$_2$(BO$_3$)$_2$. Experiments find a weak first-order
transition, which simulations of relevant microscopic models can reproduce. The
origin of this behaviour has been a matter of considerable debate for several
years. In this work, we demonstrate that the nature of the deconfined quantum
critical point can be best understood in terms of a novel dynamical mechanism,
termed Nordic walking. Nordic walking denotes a renormalisation group flow
arising from a beta function that is flat over a range of couplings. This gives
rise to a logarithmic flow that is faster than the well-known walking
behaviour, associated with the annihilation and complexification of fixed
points, but still significantly slower than the generic running of couplings.
The Nordic-walking mechanism can thus explain weak first-order transitions, but
may also play a role in high-energy physics, where it could solve hierarchy
problems.
We analyse the Wess-Zumino-Witten field theory pertinent to deconfined
quantum critical points with a topological term in 2+1 dimensions. To this end,
we construct an advanced functional renormalisation group approach based on
higher-order regulators. We thereby calculate the beta function directly in 2+1
dimensions and provide evidence for Nordic walking.
Unlike unitary dynamics, measurements of a subsystem can induce long-range
entanglement via quantum teleportation. The amount of measurement-induced
entanglement or mutual information depends jointly on the measurement basis and
the entanglement structure of the state (before measurement), and has
operational significance for whether the state is a resource for
measurement-based quantum computing, as well as for the computational
complexity of simulating the state using quantum or classical computers. In
this work, we examine entropic measures of measurement-induced entanglement
(MIE) and information (MII) for the ground-states of quantum many-body systems
in one- and two- spatial dimensions. From numerical and analytic analysis of a
variety of models encompassing critical points, quantum Hall states, string-net
topological orders, and Fermi liquids, we identify universal features of the
long-distance structure of MIE and MII that depend only on the underlying phase
or critical universality class of the state. We argue that, whereas in $1d$ the
leading contributions to long-range MIE and MII are universal, in $2d$, the
existence of a teleportation transition for finite-depth circuits implies that
trivial $2d$ states can exhibit long-range MIE, and the universal features lie
in sub-leading corrections. We introduce modified MIE measures that directly
extract these universal contributions. As a corollary, we show that the leading
contributions to strange-correlators, used to numerically identify topological
phases, are in fact non-universal in two or more dimensions, and explain how
our modified constructions enable one to isolate universal components. We
discuss the implications of these results for classical- and quantum-
computational simulation of quantum materials.
We investigate in detail the $\nu=+1$ displacement-field-tuned interacting
phase diagram of $L=3,4,5,6,7$ layer rhombohedral graphene aligned to hBN
(R$L$G/hBN). Our calculations account for the 3D nature of the Coulomb
interaction, the inequivalent stacking orientations $\xi=0,1$, the effects of
the filled valence bands, and the choice of `interaction scheme' for specifying
the many-body Hamiltonian. We show that the latter has a dramatic impact on the
Hartree-Fock phase boundaries and the properties of the phases, including for
pentalayers (R5G/hBN) with large displacement field $D$ where recent
experiments observed a Chern insulator at $\nu=+1$ and fractional Chern
insulators for $\nu<1$. In this large $D$ regime, the low-energy conduction
bands are polarized away from the aligned hBN layer, and are hence
well-described by the folded bands of moir\'eless rhombohedral graphene at the
non-interacting level. Despite this, the filled valence bands develop
moir\'e-periodic charge density variations which can generate an effective
moir\'e potential, thereby explicitly breaking the approximate continuous
translation symmetry in the conduction bands, and leading to contrasting
electronic topology in the ground state for the two stacking arrangements.
Within time-dependent Hartree-Fock theory, we further characterize the strength
of the moir\'e pinning potential in the Chern insulator phase by computing the
low-energy $\mathbf{q}=0$ collective mode spectrum, where we identify competing
gapped pseudophonon and valley magnon excitations. Our results emphasize the
importance of careful examination of both the single-particle and interaction
model for a proper understanding of the correlated phases in R$L$G/hBN.
Eugene Wigner predicted long ago that when the Coulomb interactions between
electrons become much stronger than their kinetic energy, electrons crystallize
into a closely packed lattice. A variety of two-dimensional systems have shown
evidence for Wigner crystals; however, a spontaneously formed classical or
quantum Wigner crystal (WC) has never been directly visualized. Neither the
identification of the WC symmetry nor direct investigation of its melting has
been accomplished. Here we use high-resolution scanning tunneling microscopy
(STM) measurements to directly image a magnetic field-induced electron WC in
Bernal-stacked bilayer graphene (BLG), and examine its structural properties as
a function of electron density, magnetic field, and temperature. At high fields
and the lowest temperature, we observe a triangular lattice electron WC in the
lowest Landau Level (LLL) of BLG. The WC possesses the expected lattice
constant and is robust in a range of filling factors between $\nu\sim$ 0.13 and
$\nu\sim$ 0.38 except near fillings where it competes with fractional quantum
Hall (FQH) states. Increasing the density or temperature results in the melting
of the WC into a liquid phase that is isotropic but has a modulated structure
characterized by the WC's Bragg wavevector. At low magnetic fields, the WC
unexpectedly transitions into an anisotropic stripe phase, which has been
commonly anticipated to form in higher LLs. Analysis of individual lattice
sites reveals signatures that may be related to the quantum zero-point motion
of electrons in the WC lattice.
The recent constructions of flat moir\'e minibands in specifically twisted
multilayer graphene and twisted transition metal dichalcogenides (TMDs) have
facilitated the observation of strong correlations with a convenient
tunability. These correlations in flat bands result in the band dispersion
heavily influenced by carrier densities, leading to filling-dependent
quasiparticle band renormalizations. Particularly, in magic-angle twisted
bilayer graphene (MATBG), the band structure--including the quasiparticle
energy and wavefunction--is crucial in understanding the correlated properties.
Previous theoretical studies have demonstrated the presence of a
time-reversal-even charge Hall counterflow in response to a direct current (DC)
electric field in twisted bilayers as chiral structures. In this study, we show
that such layer Hall counterflow can serve as a sensitive probe for MATBG model
parameters, which are currently ambiguous as a result of unavoidable structural
relaxation and twist-angle disorder. We present the layer Hall counterflow and
the associated in-plane magnetization for three different MATBG continuum
models, based on which many-body interacting models have been widely applied to
study strong correlations in MATBG. At the single-particle level, our findings
indicate notable differences in layer-projected Hall conductivity, both in
magnitude and sign, between different MATBG continuum models. Furthermore, our
self-consistent Hartree calculations, performed on each of these
single-particle continuum models, reveal renormalized layer-projected Hall
conductivity by the self-consistent Hartree field.
The qualitative reliability of the dynamical mean field theory (DMFT) is
investigated for systems in which either the actual carrier density or the
effective carrier density is low, by comparing the exact perturbative and
dynamical mean field expressions of electron scattering rates and optical
conductivities. We study two interacting systems: tight binding models in which
the chemical potential is near a band edge and Dirac systems in which the
chemical potential is near the Dirac point. In both systems it is found that
DMFT underestimates the low frequency, near-Fermi surface single particle
scattering rate by a factor proportional to the particle density. The
quasiparticle effective mass is qualitatively incorrect for the low density
tight binding model but not necessarily for Dirac systems. The dissipative part
of the optical conductivity is more subtle: in the exact calculation vertex
corrections, typically neglected in DMFT calculations, suppress the low
frequency optical absorption, compensating for some of the DMFT underestimate
of the scattering rate. The role of vertex corrections in calculating the
conductivity for Dirac systems is clarified and a systematic discussion is
given of the approach to the Galilean/Lorentz invariant low density limit.
Relevance to recent calculations related to Weyl metals is discussed.
Magic-angle twisted bilayer graphene (MATBG) combines in one single material
different phases like insulating, metallic and superconducting. These phases
and their in-situ tunability make MATBG an important platform for the
fabrication of superconducting devices. We realize a split gate-defined
geometry which enables us to tune the width of a superconducting channel formed
in MATBG. We observe a smooth transition from superconductivity to highly
resistive transport by progressively reducing the channel width using the split
gates or by reducing the density in the channel. Using the gate-defined
constriction, we control the flow of the supercurrent, either guiding it
through the constriction or throughout the whole device or even blocking its
passage completely. This serves as a foundation for developing quantum
constriction devices like superconducting quantum point contacts, quantum dots,
and Cooper-pair boxes in MATBG.
Complex tissue flows in epithelia are driven by intra- and inter-cellular
processes that generate, maintain, and coordinate mechanical forces. There has
been growing evidence that cell shape anisotropy, manifested as nematic order,
plays an important role in this process. Here we extend a nematic vertex model
by replacing substrate friction with internal viscous dissipation, of relevance
to epithelia not supported by a substrate or the extracellular matrix, such as
many early-stage embryos. When coupled to cell shape anisotropy, the internal
viscous dissipation allows for long-range velocity correlations and thus
enables the spontaneous emergence of flows with a large degree of
spatiotemporal organisation. We demonstrate sustained flow in epithelial sheets
confined to a channel, thus providing a link between the dynamical behaviour of
continuum active nematics and the cell-level vertex model of tissue dynamics.
Twisted vdW quantum materials have emerged as a rapidly developing field of
2D semiconductors. These materials establish a new central research area and
provide a promising platform for studying quantum phenomena and investigating
the engineering of novel optoelectronic properties such as single-photon
emission, non-linear optical response, magnon physics, and topological
superconductivity. These captivating electronic and optical properties result
from, and can be tailored by, the interlayer coupling using moir\'e patterns
formed by vertically stacking atomic layers with controlled angle
misorientation or lattice mismatch. Their outstanding properties and the high
degree of tunability position them as compelling building blocks for both
compact quantum-enabled devices and classical optoelectronics. This article
offers a comprehensive review of recent advancements in the understanding and
manipulation of twisted van der Waals structures and presents a survey of the
state-of-the-art research on moir\'e superlattices, encompassing
interdisciplinary interests. It delves into fundamental theories, synthesis and
fabrication, and visualization techniques, and the wide range of novel physical
phenomena exhibited by these structures, with a focus on their potential for
practical device integration in applications ranging from quantum information
to biosensors, and including classical optoelectronics such as modulators,
light emitting diodes (LEDs), lasers, and photodetectors. It highlights the
unique ability of moir\'e superlattices to connect multiple disciplines,
covering chemistry, electronics, optics, photonics, magnetism, topological and
quantum physics. This comprehensive review provides a valuable resource for
researchers interested in moir\'e superlattices, shedding light on their
fundamental characteristics and their potential for transformative applications
in various fields.
Gapless topological boundary states characterize nontrivial topological
phases arising from the bulk-boundary correspondence in symmetry-protected
topological materials, such as the emergence of helical edge states in a
two-dimensional $\mathbb{Z}_2$ topological insulator. However, the
incorporation of symmetry-breaking perturbation terms in the Hamiltonian leads
to the gapping of these edge bands, resulting in missing these crucial
topological boundary states. In this work, we systematically investigate the
robustness of bulk-boundary correspondence in the quantum spin Hall insulator
via recently introduced feature spectrum topology. Our findings present a
comprehensive understanding of feature-energy duality, illustrating that the
aggregate number of gapless edge states in the energy-momentum ($\it{E-k}$) map
and the non-trivial edge states in the $\hat{S}_z$ feature spectrum equals the
spin Chern number of multilayer quantum spin Hall insulator. We identify a van
der Waals material bismuth bromide $\rm(Bi_4Br_4)$ as a promising candidate
through first-principles calculations. Our work not only unravels the
intricacies of bulk-boundary correspondence but also charts a course for
exploring quantum spin Hall insulators with high spin-Chern number.
Sila-cyclic rings are a class of organosilicon cyclic compounds and have
abundant application in organic chemistry and materials science. However, it is
still challenging to synthesize compounds with sila-cyclic rings in solution
chemistry due to their low solubility and high reactivity. Recently, on-surface
synthesis was introduced into organosilicon chemistry as 1,4- disilabenzene
bridged nanostructures were obtained via coupling between bromo-substituted
molecules and silicon atoms on Au(111). Here, we extend this strategy for
syntheses of silole derivatives and graphene nanoribbons with eight-membered
sila-cyclic rings from 2,2',6,6'- tetrabromobiphenyl and
1,4,5,8-tetrabromonaphthalene on Au(111), respectively. Their structures and
electronic properties were investigated by a combination of scanning tunneling
microscopy/spectroscopy and density functional theory calculations. This work
demonstrates a generality of this synthesis strategy to fabricate various
silicon incorporated nanostructures.
Chirality is a ubiquitous phenomenon in which a symmetry between left- and
right-handed objects is broken, examples in nature ranging from subatomic
particles and molecules to living organisms. In particle physics, the weak
force is responsible for the symmetry breaking and parity violation in beta
decay, but in condensed matter systems interactions that lead to chirality
remain poorly understood. Here, we unravel the mechanism of chiral charge
density wave formation in the transition-metal dichalcogenide 1T-TiSe2. Using
representation analysis, we show that charge density modulations and ionic
displacements, which transform as a continuous scalar field and a vector field
on a discrete lattice, respectively, follow different irreducible
representations of the space group, despite the fact that they propagate with
the same wave-vectors and are strongly coupled to each other. This
charge-lattice symmetry frustration is resolved by further breaking of all
symmetries not common to both sectors through induced lattice distortions, thus
leading to chirality. Our theory is verified using Raman spectroscopy and
inelastic x-ray scattering, which reveal that all but translation symmetries
are broken at a level not resolved by state-of-the-art diffraction techniques.
Spintronics has emerged as a viable alternative to traditional electronics
based technologies in the past few decades. While on one hand, the discovery of
topological phases of matter with protected spin-polarized states has opened up
exciting prospects, recent revelation of intriguing non-relativistic spin
splitting in collinear antiferromagnetic materials with unique symmetries
facilitate a wide possibility of realizing both these features simultaneously.
In this work, we report the co-existence of these two intriguing properties
within a single material: GdAlSi. It crystallizes in a body-centered tetragonal
structure with a non-centrosymmetric space group $I4_{1}md$ ($109$). The
magnetization data indicates antiferromagnetic ordering with an ordering
temperature ($T_N$) 32 K. Ab-initio calculations reveal GdAlSi to be a
collinear antiferromagnetic Weyl semimetal with an unconventional,
momentum-dependent spin splitting, also referred to as altermagnet.
Angle-resolved photoemission spectroscopy measurements on GdAlSi single
crystals subsequently confirm the presence of Fermi arcs, a distinctive
hallmark of Weyl semimetals. Electric and magnetic multipole analysis provides
a deeper understanding of the symmetry-mediated, momentum-dependent spin
splitting, which has strictly non-relativistic origin. To the best of our
knowledge, such co-existence of unconventional antiferromagnetic order and
non-trivial topology is unprecedented and has never been observed before in a
single material, rendering GdAlSi a special and promising candidate material.
We propose a device harnessing these features, poised to enable practical and
efficient topotronic applications.
Using scanning tunneling microscopy (STM), low energy electron diffraction
(LEED), and density functional theory (DFT), we demonstrate the formation of
quasicrystalline gallium adlayer on icosahedral ($i$)-Al-Pd-Mn. Quasiperiodic
motifs are evident in the STM topography images, including the Ga white flower
(GaWF) and $\tau$ inflated GaWF ($\tau$-GaWF), where $\tau$ is the golden mean.
A larger and more complicated ring motif is also identified, comprised of a
bright center and an outer ring of pentagons. The fast Fourier transform of the
STM images exhibits distinct quasiperiodic spots, thereby establishing
quasiperiodicity on a length scale of $\sim$350 nm. Based on our DFT
calculations, the preferred adsorption sites of Ga on i-Al-Pd-Mn are determined
to be either the Mn atoms at the center of the Penrose P1 tile or the vertices
of the P1 tile containing Pd atoms at the center of a cluster of 5 Al atoms
(5-Al). The GaWF motif is modeled by an inner 6 atom Ga cluster (6-Ga) around
the central Mn atom and an outer ring of 5 Ga atoms adsorbed at the centers of
the 5-Al clusters, both having pentagonal symmetry. The $\tau$-GaWF motif is
modeled by the 6-Ga arranged on the $\tau$-P1 tiling, while the ring motif is
modeled by Ga atoms adsorbed at the center of 5-Al clusters above a Pd atom.
The side lengths and diameters of the GaWF, $\tau$-GaWF, and the ring motifs
are $\tau$ scaled and show excellent agreement with the DFT-based models. An
additional indication of the quasiperiodic characteristics of the Ga monolayer
is the 5-fold LEED patterns that were detected throughout the entire range of
beam energy that was measured.
We propose relativistic Luttinger fermions as a new ingredient for the
construction of fundamental quantum field theories. We construct the
corresponding Clifford algebra and the spin metric for relativistic invariance
of the action using the spin-base invariant formalism. The corresponding
minimal spinor has 32 complex components, matching with the degrees of freedom
of a standard-model generation including a right-handed neutrino. The resulting
fermion fields exhibit a canonical scaling different from Dirac fermions and
thus support the construction of novel relativistic and perturbatively
renormalizable, interacting quantum field theories. In particular, new
asymptotically free self-interacting field theories can be constructed,
representing first examples of high-energy complete quantum field theories
based on pure matter degrees of freedom. Gauge theories with relativistic
Luttinger fermions exhibit a strong paramagnetic dominance, requiring large
nonabelian gauge groups to maintain asymptotic freedom. We comment on the
possibility to use Luttinger fermions for particle physics model building and
the expected naturalness properties of such models.
As a distinctive feature unique to non-Hermitian systems, non-Hermitian skin
effect displays fruitful exotic phenomena in one or higher dimensions,
especially when conventional topological phases are involved. Among them,
hybrid skin-topological effect is theoretically proposed recently, which
exhibits anomalous localization of topological boundary states at
lower-dimensional boundaries accompanied by extended bulk states. Here we
experimentally realize the hybrid skin-topological effect in a non-Hermitian
phononic crystal. The phononic crystal, before tuning to be non-Hermitian, is
an ideal acoustic realization of the Kane-Mele model, which hosts gapless
helical edge states at the boundaries. By introducing a staggered distribution
of loss, the spin-dependent edge modes pile up to opposite corners, leading to
a direct observation of the spin-dependent hybrid skin-topological effect. Our
work highlights the interplay between topology and non-Hermiticity and opens
new routes to non-Hermitian wave manipulations.
Bulk-boundary correspondences (BBCs) remain the central topic in modern
condensed matter physics, and are gaining increasing interests with the recent
discovery of non-Hermitian skin effects. However, there still exist profound
features of BBCs that are beyond the existing framework. Here, we report the
unexpected behavior of BBC when the Hamiltonian contains term of the form
$d_0(k) I$, which serves as a momentum dependent energy shift. For Hermitian
cases, momentum dependent energy shift can force the system to be semimetal,
where topological phase transitions can take place with the upper and the lower
bands keeping untouched. The proper modified BBC should be reconstructed from
the perspective of the direct band gap. In non-Hermitian cases, skin effects
are found to be capable of coexisting with the preserved BBC, of which the
process can be greatly facilitated by the complex $d_0(k)I$. Remarkably, such
results can be led a further step and contrary to the intuitive consideration,
the modified BBC in Hermitian systems can be restored to be conventional by
including extra non-Hermiticity. The physical origin for these phenomena lies
in that $d_0(k)I$ can drastically change the point gap topology. Finally, the
corresponding experimental simulations are proposed via the platforms of
electric circuits.
The 3D folding of a mammalian gene can be studied by a polymer model, where
the chromatin fibre is represented by a semiflexible polymer which interacts
with multivalent proteins, representing complexes of DNA-binding transcription
factors and RNA polymerases. This physical model leads to the natural emergence
of clusters of proteins and binding sites, accompanied by the folding of
chromatin into a set of topologies, each associated with a different network of
loops. Here we combine numerics and analytics to first classify these networks
and then find their relative importance or statistical weight, when the
properties of the underlying polymer are those relevant to chromatin. Unlike
polymer networks previously studied, our chromatin networks have finite average
distances between successive binding sites, and this leads to giant differences
between the weights of topologies with the same number of edges and nodes but
different wiring. These weights strongly favour rosette-like structures with a
local cloud of loops with respect to more complicated non-local topologies. Our
results suggest that genes should overwhelmingly fold into a small fraction of
all possible 3D topologies, which can be robustly characterised by the
framework we propose here.
Magnetic skyrmions hold great promise for realizing compact and stable memory
devices that can be manipulated at very low energy costs via electronic current
densities. In this work, we extend a recently introduced method to describe
classical skyrmion textures coupled to dynamical itinerant electrons. In this
scheme, the electron dynamics is described via nonequilibrium Green's functions
(NEGF) within the generalized Kadanoff-Baym ansatz, and the classical spins are
treated via the Landau-Lifshitz-Gilbert equation. The framework is here
extended to open systems, by the introduction of a non-interacting
approximation to the collision integral of NEGF. This, in turn, allows us to
perform computations of the real-time response of skyrmions to electronic
currents in large quantum systems coupled to electronic reservoirs, which
exhibit a linear scaling in the number of time steps. We use this approach to
investigate how electronic spin currents and dilute spin disorder affects
skyrmion transport and the skyrmion Hall drift. Our results show that the
skyrmion dynamics is sensitive to the specific form of spin disorder, such that
different disorder configurations leads to qualitatively different skyrmion
trajectories for the same applied bias. This sensitivity arises from the local
spin dynamics around the magnetic impurities, a feature that is expected not to
be well captured by phenomenological or spin-only descriptions. At the same
time, our findings illustrate the potential of engineering microscopic impurity
patterns to steer skyrmion trajectories.
Topological magnon insulators support chiral edge excitations, whose lack of
electric charge makes them notoriously difficult to detect experimentally. We
show that relativistic magnetoelectric coupling universally renders chiral edge
magnons electrically active, thereby facilitating electrical probes of magnon
topology. Considering a two-dimensional out-of-plane magnetized topological
magnon insulator, we predict a fluctuation-activated electric polarization
perpendicular to the sample edges. Furthermore, the chiral topological
electromagnons give rise to a unique in-gap signal in electrical absorption
experiments. These results suggest THz spectroscopy as a promising probe for
topological magnons.
We investigate the energy levels of fermions within a circular graphene
quantum dot (GQD) subjected to external magnetic and Aharonov-Bohm fields.
Solving the eigenvalue equation for two distinct regions allows us to determine
the eigenspinors for the valleys $K$ and $K^\prime$. By establishing the
continuity of eigenspinors at the GQD interface, we derive an equation that
reveals the reliance of energy levels on external physical parameters. Our
observations suggest that the symmetry of energy levels hinges on the selected
physical parameters. We observe that at low magnetic fields, the energy levels
display degeneracy, which diminishes as the field strength increases,
coinciding with the convergence of energy levels toward the Landau levels. We
illustrate that the introduction of a magnetic flux into the GQD leads to the
creation of an energy gap, extending the trapping time of electrons without
perturbing the system. Conversely, the addition of gap energy widens the band
gap, disrupting the system's symmetry by introducing new energy levels.
Thermal rectification devices can be important for various thermal management
applications. For oscillator chains, thermal rectification was observed when
masses are distributed non-uniformly. Leaning on the importance of topological
materials, we consider here a simple vibrational topological system, the binary
isotope superlattice (BISL). We show that the BISL can be mapped exactly onto
the Su-Schrieffer-Heeger (SSH) model, which has different topological phases,
including topological edge sates. For the case, where there is a single
topological edge state, we show that the BISL exhibits thermal rectification in
the presence of a small nonlinear term. Thermal transport is computed using
temperature reservoirs connected to both extremities. These results have
implications for other classes of topological phonon systems.
Ligands are the key to almost any strategy in the assembly of programmable
nanocrystals (or nanoparticles) and must be accurately considered in any
predictive model. Hard Spheres (or Shapes) provide the simplest and yet quite
successful approach to assembly, with remarkable sophisticated predictions
verified in experiments. There are, however, many situations where hard
spheres/shapes predictions fail. This prompts three important questions: {\em
In what situations should hard spheres/shapes models be expected to work?} and
when they do not work, {\em Is there a general model that successfully corrects
hard sphere/shape predictions?} and given other successful models where ligands
are included explicitly, and of course, numerical simulations, {\em can we
unify hard sphere/shape models, explicit ligand models and all atom
simulations?}. The Orbifold Topological Model (OTM) provides a positive answer
to these three questions. In this paper, I give a detailed review of OTM,
describing the concept of ligand vortices and how it leads to spontaneous
valence and nanoparticle ``eigenshapes'' while providing a prediction of the
lattice structure, without fitting parameters, which accounts for many body
effects not captured in (two-body) potentials. I present a thorough survey of
experiments and simulations and show that, to this date, they are in full
agreement with the OTM predictions. I will conclude with a discussion on
whether NC superlattices are equilibrium structures and some significant
challenges in structure prediction.
Superconducting diode effect (SDE) with nonreciprocal supercurrent transport
has attracted intense attention recently, not only for its intriguing physics,
but also for its great application potential in superconducting circuits. It is
revealed in this work that planar Josephson junctions (JJs) based on type-II
Weyl semimetal (WSM) MoTe$_2$ can exhibit a prominent SDE due to the emergence
of asymmetric Josephson effect (AJE) in perpendicular magnetic fields. The AJE
manifests itself in a very large asymmetry in the critical supercurrents with
respect to the current direction. The sign of this asymmetry can also be
effectively modulated by the external magnetic field. Considering the special
noncentrosymmetric crystal symmetry of MoTe$_2$, this AJE is understood in
terms of the Edelstein effect, which induces a nontrivial phase shift in the
current phase relation of the junctions. Besides these, it is further
demonstrated that the rectification of supercurrent in such MoTe$_2$ JJs with
the rectification efficiency up to 50.4%, unveiling the great application
potential of WSMs in superconducting electronics.
A dimerized chain of dipolar emitters strongly coupled to a multimode optical
waveguide cavity is studied. By integrating out the photonic degrees of freedom
of the cavity, the system is recast in a two-band model with an effective
coupling, so that it mimics a variation of the paradigmatic
Su-Schrieffer-Heeger model, which features a nontrivial topological phase and
hosts topological edge states. In the strong-coupling regime, the cavity
photons hybridize the bright dipolar bulk band into a polaritonic one,
renormalizing the eigenspectrum and strongly breaking chiral symmetry. This
leads to a formal loss of the in-gap edge states present in the topological
phase while they merge into the polaritonic bulk band. Interestingly, however,
we find that bulk polaritons entering in resonance with the edge states inherit
part of their localization properties, so that multiple polaritonic edge states
are observed. Although these states are not fully localized on the edges, they
present unusual properties. In particular, due to their delocalized bulk part,
owing from their polaritonic nature, such edge states exhibit efficient
edge-to-edge transport characteristics. Instead of being degenerate, they
occupy a large portion of the spectrum, allowing one to probe them in a wide
driving frequency range. Moreover, being reminiscent of symmetry-protected
topological edge states, they feature a strong tolerance to positional
disorder.
The experimental work [J. Crossno et al., Science 351, 1058 (2016)], which
reported the violation of the Wiedemann-Franz law in monolayer graphene
characterized by a sharp peak of the Lorenz ratio at a finite temperature, has
not been fully explained. Our previous work [Y.-T. Tu and S. Das Sarma, Phys.
Rev. B 107, 085401 (2023)] provided a possible explanation through a
Boltzmann-transport model with bipolar diffusion and an energy gap possibly
induced by the substrate. In this paper, we extend our calculation to include a
weak magnetic field perpendicular to the graphene layer, which is
experimentally relevant, and may shed light on the possible violation or not of
the Wiedemann-Franz law. We find that the magnetic field enhances the size of
the peak of the Lorenz ratio but has little effect on its position, and that
the transverse component of the Lorenz ratio can be either positive or negative
depending on the parameter regime. In addition, we do the same calculation for
bilayer graphene in the presence of a magnetic field and show the qualitative
similarity with monolayer graphene. Our work should motivate
magnetic-field-dependent experiments elucidating the nature of the charge
carriers in graphene layers.
Raman spectroscopy is widely used to assess the quality of 2D materials thin
films. This report focuses on $\rm{PtSe_2}$, a noble transition metal
dichalcogenide which has the remarkable property to transit from a
semi-conductor to a semi-metal with increasing layer number. While
polycrystalline $\rm{PtSe_2}$ can be grown with various crystalline qualities,
getting insight into the monocrystalline intrinsic properties remains
challenging. We report on the study of exfoliated 1 to 10 layers $\rm{PtSe_2}$
by Raman spectroscopy, featuring record linewidth. The clear Raman signatures
allow layer-thickness identification and provides a reference metrics to assess
crystal quality of grown films.
The coherence length $\xi$ is a fundamental length scale of superconductors
which governs the sizes of Cooper pairs, vortices, Andreev bound states and
more. In existing microscopic theories of superconductivity, it is expected
that as the attractive interaction increases, $\xi$ decreases as the electrons
are bound together more strongly. In BCS theory, for example, the coherence
length is $\xi_\mathrm{BCS} = \hbar v_{F}/\Delta$, where $v_{F}$ is the Fermi
velocity and $\Delta$ is the pairing gap. It is clear that increasing $\Delta$
will shorten $\xi_\mathrm{BCS}$. However, the situation is puzzling for
superconductors with completely flat bands in which $v_{F}$ goes to zero and
$\xi_\mathrm{BCS}$ is expected to be zero. In this work, we show that the
quantum metric, which is the real part of the quantum geometric tensor, gives
rise to an anomalous contribution to the coherence length. Specifically, $\xi =
\sqrt{\xi_\mathrm{BCS}^2 +\ell_{\mathrm{qm}}^{2}}$ for a superconductor where
$\ell_{\mathrm{qm}}$ is the quantum metric contribution. In the flat band
limit, $\xi$ does not vanish but bound by $\ell_{\mathrm{qm}}$. Incredibly, for
the nontrivial flat bands with Chern number $C$, $\xi$ has a topological bound
of $\xi\geq a\sqrt{\vert C \vert/4\pi}$ where $a$ is the lattice constant.
Physically, the Cooper pair size of a superconductor cannot be squeezed down to
a size smaller than $\ell_{\mathrm{qm}}$ which is a fundamental length scale
determined by the quantum geometry of the bands. Finally, we calculate the
quantum metric contributions for the superconducting moir\'e graphene family
and show that the quantum metric effects are very important in these
superconductors.
Recent experiments have uncovered a distinctive magnetic metal in
lightly-doped multilayer graphene, coined the \textit{quarter metal}. This
quarter metal consolidates all the doped carriers, originally distributed
evenly across the four (or twelve) Fermi surfaces of the paramagnetic state,
into one expansive Fermi surface by breaking time-reversal and/or inversion
symmetry. In this work, we map out a comprehensive mean-field phase diagram of
the quarter-metal in rhombohedral trilayer graphene within the four dimensional
parameter space spanned by the density $n_e$, interlayer electric potential
$U$, external magnetic field parallel to the two-dimensional material plane
$B_{\parallel}$ and Kane-Mele spin-orbit coupling $\lambda$. We found an
annular Lifshitz phase transition and a Ising-XY phase transition and locate
these phase boundaries on the experimental phase diagram. The movement of the
Ising-XY phase boundary offers insights into $\lambda$. Our analysis reveals
that it moves along the line $\partial n_e/\partial B_{\parallel} \sim
-0.5\times 10^{11} \text{cm}^{-2}\text{T}^{-1}$ within the
$n_e$-$B_{\parallel}$ parameter space when $\lambda=30\mu$eV. Additionally, we
estimated the in-plane spin susceptibility of the valley-Ising quarter-metal
$\chi_{_\parallel}\sim 8~\mu\text{eV} ~\text{T}^{-2}$. Beyond these
quantitative findings, two general principles emerge from our study: 1) The
valley-XY quarter metal's dominance in the $n_e-U$ parameter space grows with
an increasing number of layers due to the reduce valley polarization variations
within the Fermi sea. 2) Layer polarization near the band edge plays an
important role in aiding the re-entrance of the paramagnetic state at low
density. The insights derived from the quarter metal physics may shed light on
the complex behaviors observed in other regions of the phase diagram.
The ground-state superfluid behavior of ultracold atomic Fermi gases with an
on-site attractive interaction in a quasi-two-dimensional Lieb lattice is
studied using BCS mean-field theory, within the context of BCS-BEC crossover.
We find that the flat band leads to nontrivial exotic effects. As the Fermi
level enters the flat band, both the pairing gap and the in-plane superfluid
density exhibit an unusual power law as a function of interaction, with
strongly enhanced quantum geometric effects, in addition to a dramatic increase
of compressibility as the interaction approaches the BCS limit. As the Fermi
level crosses the van Hove singularities, the character of pairing changes from
particle-like to hole-like or vice versa. We present the computed phase
diagram, in which a pair density wave state emerges at high densities with
relatively strong interaction strength.
A unidirectional "density" wave order in an otherwise isotropic environment
is guaranteed to display a smecticlike Goldstone mode. Examples of such "soft"
states include conventional smectic liquid crystals, putative
Fulde-Ferrell-Larkin-Ovchinnikov superfluids, and helical states of frustrated
bosons and spins. Here we develop generalized spin-smectic $\sigma$-models that
break $O(N)$ internal symmetry in addition to the $d$-dimensional rotational
and uniaxial translational symmetries. We explore long-wavelength properties of
such strongly fluctuating states, show that they are characterized by a
"double-power-law" static structure peak, and analyze their asymptotic
symmetry-reduced crossover to conventional low-energy modes. We also present
the associated Ginzburg-Landau theory, describing phase transition into such
spin-smectic states, and discuss experimental realization of such models.
Systems displaying quantum topological order feature robust characteristics
that are very attractive to quantum computing schemes. Topological quantum
field theories have proven to be powerful in capturing the quintessential
attributes of systems displaying topological order including, in particular,
their anyon excitations. Here, we investigate systems that lie outside this
common purview, and present a rich class of models exhibiting topological
orders with distance-dependent interacting anyons. As we illustrate, in some
instances, the gapped lowest-energy excitations are comprised of anyons that
densely cover the entire system. This leads to behaviors not typically
described by topological quantum field theories. We examine these models by
performing dualities to systems displaying conventional (i.e., Landau) orders.
Our approach enables a general method for mapping generic Landau-type theories
to dual models with topological order of the same spatial dimension. The
low-energy subspaces of our models can be made more resilient to thermal
effects than those of surface codes.
In this work, it is shown that in certain nonsymmorphic space groups,
electric polarization due to an external electric field or ferroelectric order
produces Weyl phonons.
Molybdenum disulfide, $MoS_2$, is a next-generation semiconductor and is
frequently integrated into emergent optoelectronic technologies based on
two-dimensional materials. Here, we present a method that provides direct
optical feedback on the thickness and crystallinity of sputter-deposited
$MoS_2$ down to the few-layer regime. This smart sensing enables tracking the
material's functional properties, such as excitonic response, sheet resistance,
and hardness across the amorphous-crystalline transition. To illustrate the
potential of such feedback-controlled fabrication, we realized $MoS_2$-based
hyperbolic metamaterials (HMM) with controllable optical topological
transitions and hardness.
Given the rarity of metallic systems that exhibit ferroelectric-like
transitions, it is apparently challenging to find a system that simultaneously
possesses superconductivity and ferroelectric-like structural instability.
Here, we report the observation of superconductivity at 2.4 K in a layered
semimetal SrAuBi characterized by strong spin-orbit coupling (SOC) and
ferroelectric-like lattice distortion. Single crystals of SrAuBi have been
successfully synthesized and found to show a polar-nonpolar structure
transition at 214 K, which is associated with the buckling of Au-Bi honeycomb
lattice. On the basis of the band calculations considering SOC, we found
significant Rashba-type spin splitting and symmetry-protected multiple Dirac
points near the Fermi level. We believe that this discovery opens up new
possibilities of pursuing exotic superconducting states associated with the
semimetallic band structure without space inversion symmetry and the
topological surface state with the strong SOC.

Date of feed: Wed, 20 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) **Tracking Intrinsic Non-Hermitian Skin Effect in Lossy Lattices. (arXiv:2312.11490v1 [cond-mat.other])**

Liwei Xiong, Qicheng Zhang, Xiling Feng, Yufei Leng, Min Pi, Shuaishuai Tong, Chunyin Qiu

**Essay: Where Can Quantum Geometry Lead Us?. (arXiv:2312.11516v1 [cond-mat.supr-con])**

Paivi Torma

**Phenomenology of Majorana zero modes in full-shell hybrid nanowires. (arXiv:2312.11613v1 [cond-mat.mes-hall])**

Carlos Payá, Samuel D. Escribano, Andrea Vezzosi, Fernando Peñaranda, Ramón Aguado, Pablo San-Jose, Elsa Prada

**The Nordic-walking mechanism and its explanation of deconfined pseudocriticality from Wess-Zumino-Witten theory. (arXiv:2312.11614v1 [cond-mat.str-el])**

Bilal Hawashin, Astrid Eichhorn, Lukas Janssen, Michael M. Scherer, Shouryya Ray

**Universal structure of measurement-induced information in many-body ground states. (arXiv:2312.11615v1 [quant-ph])**

Zihan Cheng, Rui Wen, Sarang Gopalakrishnan, Romain Vasseur, Andrew C. Potter

**Moir\'e Fractional Chern Insulators III: Hartree-Fock Phase Diagram, Magic Angle Regime for Chern Insulator States, the Role of the Moir\'e Potential and Goldstone Gaps in Rhombohedral Graphene Superlattices. (arXiv:2312.11617v1 [cond-mat.str-el])**

Yves H. Kwan, Jiabin Yu, Jonah Herzog-Arbeitman, Dmitri K. Efetov, Nicolas Regnault, B. Andrei Bernevig

**Direct observation of a magnetic field-induced Wigner crystal. (arXiv:2312.11632v1 [cond-mat.mes-hall])**

Yen-Chen Tsui, Minhao He, Yuwen Hu, Ethan Lake, Taige Wang, Kenji Watanabe, Takashi Taniguchi, Michael P. Zaletel, Ali Yazdani

**Layer Hall counterflow as a model probe of magic-angle twisted bilayer graphene. (arXiv:2312.11662v1 [cond-mat.mes-hall])**

Jihang Zhu, Dawei Zhai, Cong Xiao, Wang Yao

**Dynamical Mean Field Theory for Low Density and Dirac Materials. (arXiv:2312.11693v1 [cond-mat.str-el])**

Anqi Mu, Zhiyuan Sun, Andrew J. Millis

**Gate-defined superconducting channel in magic-angle twisted bilayer graphene. (arXiv:2312.11698v1 [cond-mat.mes-hall])**

Giulia Zheng, Elías Portolés, Alexandra Mestre-Torá, Marta Perego, Takashi Taniguchi, Kenji Watanabe, Peter Rickhaus, Folkert K. de Vries, Thomas Ihn, Klaus Ensslin, Shuichi Iwakiri

**From Dry to Wet Vertex Model Dynamics: Generating Sustained Flows. (arXiv:2312.11756v1 [cond-mat.soft])**

Jan Rozman, Chaithanya K. V. S., Julia M. Yeomans, Rastko Sknepnek

**Twisted van der Waals Quantum Materials: Fundamentals, Tunability and Applications. (arXiv:2312.11757v1 [cond-mat.mtrl-sci])**

Xueqian Sun, Manuka Suriyage, Ahmed Khan, Mingyuan Gao, Jie Zhao, Boqing Liu, Mehedi Hasan, Sharidya Rahman, Ruosi Chen, Ping Koy Lam, Yuerui Lu

**Feature-energy duality of topological boundary states in multilayer quantum spin Hall insulator. (arXiv:2312.11794v1 [cond-mat.mtrl-sci])**

Yueh-Ting Yao, Xiaoting Zhou, Yi-Chun Hung, Hsin Lin, Arun Bansil, Tay-Rong Chang

**On-Surface Synthesis of Silole and Disilacyclooctaene Derivatives. (arXiv:2312.11959v1 [cond-mat.mtrl-sci])**

Kewei Sun, Lauri Kurki, Orlando J. Silveira, Tomohiko Nishiuchi, Takashi Kubo, Ondřej Krejčí, Adam S. Foster, Shigeki Kawai

**Origin of chirality in transition-metal dichalcogenides. (arXiv:2312.11979v1 [cond-mat.str-el])**

Kwangrae Kim, Hyun-Woo J. Kim, Seunghyeok Ha, Hoon Kim, Jin-Kwang Kim, Jaehwon Kim, Hyunsung Kim, Junyoung Kwon, Jihoon Seol, Saegyeol Jung, Changyoung Kim, Ahmet Alatas, Ayman Said, Michael Merz, Matthieu Le Tacon, Jin Mo Bok, Ki-Seok Kim, B. J. Kim

**GdAlSi: An antiferromagnetic topological Weyl semimetal with non-relativistic spin splitting. (arXiv:2312.11980v1 [cond-mat.str-el])**

Jadupati Nag, Bishal Das, Sayantika Bhowal, Yukimi Nishioka, Barnabha Bandyopadhyay, Shiv Kumar, Kenta Kuroda, Akio Kimura, K. G. Suresh, Aftab Alam

**Quasiperiodic gallium adlayer on i-Al-Pd-Mn. (arXiv:2312.12005v1 [cond-mat.mtrl-sci])**

Pramod Bhakuni, Marian Krajčí, Sudipta Roy Barman

**Quantum field theories of relativistic Luttinger fermions. (arXiv:2312.12058v1 [hep-th])**

Holger Gies, Philip Heinzel, Johannes Laufkötter, Marta Picciau

**Spin-dependent localization of helical edge states in a non-Hermitian phononic crystal. (arXiv:2312.12060v1 [cond-mat.mes-hall])**

Junpeng Wu, Riyi Zheng, Jialuo Liang, Manzhu Ke, Jiuyang Lu, Weiyin Deng, Xueqin Huang, Zhengyou Liu

**Bulk-boundary correspondence in topological systems with the momentum dependent energy shift. (arXiv:2312.12127v1 [cond-mat.quant-gas])**

Huan-Yu Wang, Zhen-Biao Yang, Wu-Ming Liu

**Topological spectra and entropy of chromatin loop networks. (arXiv:2312.12159v1 [physics.bio-ph])**

Andrea Bonato, Dom Corbett, Sergey Kitaev, Davide Marenduzzo, Alexander Morozov, Enzo Orlandini

**Microscopic theory of current-induced skyrmion transport and its application in disordered spin textures. (arXiv:2312.12201v1 [cond-mat.mes-hall])**

Emil Östberg, Emil Viñas Boström, Claudio Verdozzi

**Electrical Activity of Topological Chiral Edge Magnons. (arXiv:2312.12316v1 [cond-mat.mes-hall])**

Robin R. Neumann, Jürgen Henk, Ingrid Mertig, Alexander Mook

**Energy levels of gapped graphene quantum dots in external fields. (arXiv:2312.12324v1 [cond-mat.mes-hall])**

Ahmed Bouhlal, Mohammed El Azar, Ahmed Siari, Ahmed Jellal

**Thermal rectification with topological edge states. (arXiv:2312.12374v1 [cond-mat.mes-hall])**

Abdulla Alseiari, Michael Hilke

**Nanocrystal Programmable Assembly Beyond Hard Spheres (or Shapes) and Other (Simple) Potentials. (arXiv:2312.12421v1 [cond-mat.soft])**

Alex Travesset

**Edelstein effect induced superconducting diode effect in inversion symmetry breaking MoTe$_2$ Josephson junctions. (arXiv:2303.07701v2 [cond-mat.supr-con] UPDATED)**

Pingbo Chen, Gongqi Wang, Bicong Ye, Jinhua Wang, Liang Zhou, Zhenzhong Tang, Le Wang, Jiannong Wang, Wenqing Zhang, Jiawei Mei, Weiqiang Chen, Hongtao He

**Multiple polaritonic edge states in a Su-Schrieffer-Heeger chain strongly coupled to a multimode cavity. (arXiv:2305.06956v2 [cond-mat.mes-hall] UPDATED)**

Thomas F. Allard, Guillaume Weick

**Wiedemann-Franz law in graphene in the presence of a weak magnetic field. (arXiv:2307.05477v2 [cond-mat.mes-hall] UPDATED)**

Yi-Ting Tu, Sankar Das Sarma

**Raman spectroscopy of monolayer to bulk PtSe2 exfoliated crystals. (arXiv:2307.15520v4 [cond-mat.mtrl-sci] UPDATED)**

Marin Tharrault, Eva Desgué, Dominique Carisetti, Bernard Plaçais, Christophe Voisin, Pierre Legagneux, Emmanuel Baudin

**Anomalous Coherence Length in Superconductors with Quantum Metric. (arXiv:2308.05686v3 [cond-mat.supr-con] UPDATED)**

Jin-Xin Hu, Shuai A. Chen, K. T. Law

**Quarter-Metal Phases in Multilayer Graphene: Ising-XY and Annular Lifshitz Transitions. (arXiv:2310.10759v2 [cond-mat.mes-hall] UPDATED)**

Mainak Das, Chunli Huang

**Flat band effects on the ground-state BCS-BEC crossover in atomic Fermi gases in a quasi-two-dimensional Lieb lattice. (arXiv:2310.12944v2 [cond-mat.quant-gas] UPDATED)**

Hao Deng, Chuping Li, Yuxuan Wu, Lin Sun, Qijin Chen

**$O(N)$ smectic $\sigma$-model. (arXiv:2310.13046v2 [cond-mat.stat-mech] UPDATED)**

Tzu-Chi Hsieh, Leo Radzihovsky

**Topological Orders Beyond Topological Quantum Field Theories. (arXiv:2311.03353v2 [cond-mat.mes-hall] UPDATED)**

P. Vojta, G. Ortiz, Z. Nussinov

**Polarization-induced Weyl phonons in nonsymmorphic crystals. (arXiv:2312.07493v2 [cond-mat.mes-hall] UPDATED)**

Sahal Kaushik

**Smart sensing of the multifunctional properties of magnetron sputtered $MoS_2$ across the amorphous-crystalline transition. (arXiv:2312.10180v2 [cond-mat.mtrl-sci] UPDATED)**

Jose L. Ocana-Pujol, Rebecca A. Gallivan, Ramon Camilo Dominguez Ordoñez, Nikolaus Porenta, Arnold Müller, Christof Vockenhuber, Ralph Spolenak, Henning Galinski

**Superconductivity in a ferroelectric-like topological semimetal SrAuBi. (arXiv:2312.10354v2 [cond-mat.supr-con] UPDATED)**

Hidefumi Takahashi, Tomohiro Sasaki, Akitoshi Nakano, Kazuto Akiba, Masayuki Takahashi, Alex H. Mayo, Masaho Onose, Tatsuo C. Kobayashi, Shintaro Ishiwata

Found 7 papers in prb Tight bosonic analogs of free-fermionic symmetry-protected topological phases, and their associated edge-localized excitations, have long evaded the grasp of condensed-matter and AMO physics. In this paper, building on our initial exploration [Phys. Rev. Lett. We recently showed that spin fluctuations of noncoplanar magnetic states can induce topological superconductivity in an adjacent normal metal [Mæland We report transport studies on the layered van der Waals topological crystalline insulator ${\mathrm{Ta}}_{2}{\mathrm{Pd}}_{3}{\mathrm{Te}}_{5}$. The temperature-dependent resistance at high temperature is dominated by a bulk insulating gap and tends to saturate at low temperatures. Low-temperature … We investigate the electronic properties of a hybrid system that comprises single-bilayer graphene structures subjected to a perpendicular magnetic field. Specifically, our focus is on the behavior exhibited by the zigzag boundaries of the junction, namely, zigzag-1 (ZZ1) and zigzag-2 (ZZ2), using t… Valley coupling is proposed to construct a spatially separated two-parameter pump based on the O- or Y-shaped Kekulé (Kek) graphene superlattices (GSs) with a sandwiched graphene layer. It is shown that for the O-shaped Kek GS pumping structure, pumped charges with an integer number can be obtained … We study a quasistatically driven random-field Ising model (RFIM) at zero temperature with interactions mediated by the long-range anisotropic Eshelby kernel. Analogously to amorphous solids at their yielding transition, and differently from ferromagnetic and dipolar RFIMs, the model shows a discont… This study conducts experimental exploration into a system of two-dimensional Dirac fermions utilizing a critical-thickness HgTe quantum well in weak magnetic fields. The formation and evolution of Shubnikov–de Haas oscillations in the magnetotransport and the capacitive response are studied, comple…

Date of feed: Wed, 20 Dec 2023 04:16:55 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) **Topological zero modes and edge symmetries of metastable Markovian bosonic systems**

Vincent P. Flynn, Emilio Cobanera, and Lorenza Viola

Author(s): Vincent P. Flynn, Emilio Cobanera, and Lorenza Viola**127**, 245701 (2021)], we identify a broa…

[Phys. Rev. B 108, 214312] Published Tue Dec 19, 2023

**Topological superconductivity mediated by magnons of helical magnetic states**

Kristian Mæland, Sara Abnar, Jacob Benestad, and Asle Sudbø

Author(s): Kristian Mæland, Sara Abnar, Jacob Benestad, and Asle Sudbø*et al.*, Phys. Rev. Lett. **130**, 156002 (2023)]. The noncolinear nature of the spins was found to be essential for this result, while the necessity of n…

[Phys. Rev. B 108, 224515] Published Tue Dec 19, 2023

**Weak antilocalization in the transition metal telluride ${\mathrm{Ta}}_{2}{\mathrm{Pd}}_{3}{\mathrm{Te}}_{5}$**

Wen-He Jiao, Hang-Qiang Qiu, Wuzhang Yang, Jin-Ke Bao, Shaozhu Xiao, Yi Liu, Yuke Li, Guang-Han Cao, Xiaofeng Xu, Zhi Ren, and Peng Zhang

Author(s): Wen-He Jiao, Hang-Qiang Qiu, Wuzhang Yang, Jin-Ke Bao, Shaozhu Xiao, Yi Liu, Yuke Li, Guang-Han Cao, Xiaofeng Xu, Zhi Ren, and Peng Zhang

[Phys. Rev. B 108, 245145] Published Tue Dec 19, 2023

**Transport properties of hybrid single-bilayer graphene interfaces in a magnetic field**

Nadia Benlakhouy, Ahmed Jellal, and Michael Schreiber

Author(s): Nadia Benlakhouy, Ahmed Jellal, and Michael Schreiber

[Phys. Rev. B 108, 245419] Published Tue Dec 19, 2023

**Valley coupling constructed topological two-parameter charge pump**

Zixuan Ding, Donghao Wang, Yongchun Tao, and Mengyao Li

Author(s): Zixuan Ding, Donghao Wang, Yongchun Tao, and Mengyao Li

[Phys. Rev. B 108, 245420] Published Tue Dec 19, 2023

**Far-from-equilibrium criticality in the random-field Ising model with Eshelby interactions**

Saverio Rossi, Giulio Biroli, Misaki Ozawa, and Gilles Tarjus

Author(s): Saverio Rossi, Giulio Biroli, Misaki Ozawa, and Gilles Tarjus

[Phys. Rev. B 108, L220202] Published Tue Dec 19, 2023

**Spin splitting and disorder of Landau levels in HgTe-based Dirac fermions**

D. A. Kozlov, J. Ziegler, N. N. Mikhailov, Z. D. Kvon, and D. Weiss

Author(s): D. A. Kozlov, J. Ziegler, N. N. Mikhailov, Z. D. Kvon, and D. Weiss

[Phys. Rev. B 108, L241301] Published Tue Dec 19, 2023

Found 1 papers in pr_res The topological phases of monolayer jacutingaite (${\mathrm{Pt}}_{2}{\mathrm{HgSe}}_{3}$) under off-resonance high-frequency and high-intensity laser irradiation and staggered sublattice potential $V$ are investigated. The various steady-state phases are realized by an appropriate choice of the off-…

Date of feed: Wed, 20 Dec 2023 04:16:53 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99) **Photoinduced phases in jacutingaite monolayer**

Mohammad Alipourzadeh, Yaser Hajati, and Jamal Berakdar

Author(s): Mohammad Alipourzadeh, Yaser Hajati, and Jamal Berakdar

[Phys. Rev. Research 5, 043263] Published Tue Dec 19, 2023

Found 1 papers in nano-lett

Date of feed: Tue, 19 Dec 2023 14:16:00 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) **[ASAP] Electroluminescence as a Probe of Strong Exciton–Plasmon Coupling in Few-Layer WSe2**

Yunxuan Zhu, Jiawei Yang, Jaime Abad-Arredondo, Antonio I. Fernández-Domínguez, Francisco J. Garcia-Vidal, and Douglas NatelsonNano LettersDOI: 10.1021/acs.nanolett.3c04684

Found 1 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]+)|(flatband)|(flat.{1}band)|(LK.{1}99) **Resurgence of superconductivity and the role of dxy hole band in FeSe _{1−x}Te_{x}**

Amalia I. Coldea

Communications Physics, Published online: 19 December 2023; doi:10.1038/s42005-023-01481-w

The iron chalcogenide material FeSe1-xTex constitutes an important family of unconventional superconductors but its nematic phase was less explored due to a lack of single crystals. In this study, the authors provide a systematic study of the electronic structure for nematic FeSe1-xTex and observe that as the Te content increases a gradual shift and renormalization of the dxy orbital occurs, concomitant with the enhancement of superconductivity.