Found 27 papers in cond-mat The joint symmetry $C_{2z}T$ protects obstructed atomic insulators in 2D
translational invariant magnetic materials, where electrons form molecule
orbitals with charge centers away from the positions of atoms. The transitions
from these states to atomic insulators have to go through an intermediate
metallic phase accomplished by the emergence, evolution, and annihilation of
Dirac points. We show that, under (quenched) weak chemical potential disorder
that respects the $C_{2z}T$ symmetry on average, the intermediate metallic
phase remains delocalized, where every point in a finite transition process is
a scale-invariant critical metal in the thermodynamic limit. We thus refer to
the delocalized metallic phase as a crystalline-symmetry-associated critical
metal phase. The underlying mechanism cannot be explained by conventional
localization theories, such as weak anti-localization and topological phase
transition in the ten-fold way classification. Through a quantitative mapping
between lattice models and network models, we find that the critical metal
phase is equivalent to a quantum percolation problem with random fluxes. The
criticality can hence be understood through a semi-classical percolation
theory.
The realization of topological antiferromagnetic (AFM) solitons in real
materials is a major goal towards their use in information technology. While
they bear various advantages with respect to their ferromagnetic cousins, their
observation is scarce. Utilizing first-principles simulations, here we predict
new chiral particles in the realm of AFM topological magnetism, frustrated
multimeronic spin-textures hosted by a N\'eel magnetic state, arising in single
Mn layers directly grown on Ir(111) surface or interfaced with Pd-based films.
These topological structures are intrinsic, i.e. they form in a single AFM
material, can carry distinct topological charges and can combine in various
multimeronic sequences with enhanced stability against external magnetic
fields. We envision the frustrated N\'eel AFM multimerons as exciting
highly-sought after AFM solitons having the potential to be utilized in novel
spintronic devices hinging on non-synthetic AFM quantum materials.
One of the most appealing aspects of machine learning for material design is
its high throughput exploration of chemical spaces, but to reach the ceiling of
ML-aided exploration, more than current model architectures and processing
algorithms are required. New architectures such as Graph Neural Networks (GNNs)
have seen significant research investments recently. For heterogeneous
catalysis, defining substrate intramolecular bonds and adsorbate/substrate
intermolecular bonds is a time-consuming and challenging process. Before
applying a model, dataset pre-processing, node/bond descriptor design, and
specific model constraints have to be considered. In this work, a framework
designed to solve these issues is presented in the form of an automatic graph
representation algorithm (AGRA) tool to extract the local chemical environment
of metallic surface adsorption sites is presented. This tool is able to gather
multiple adsorption geometry datasets composed of different systems and combine
them into a single model. To show AGRA's excellent transferability and reduced
computational cost compared to other graph representation methods, it was
applied to 5 different catalytic reaction datasets and benchmarked against the
Open Catalyst Projects (OCP) graph representation method. The two ORR datasets
with O/OH adsorbates obtained 0.053 eV RMSD when combined together, whereas the
three CO2RR datasets with CHO/CO/COOH obtained an average performance of 0.088
eV RMSD. To further display the algorithm's versatility and extrapolation
ability, a model was trained on a subset combination of all 5 datasets with an
RMSD of 0.105 eV. This universal model was then used to predict a wide range of
adsorption energies and an entirely new ORR catalyst system and then verified
through Density Functional Theory calculations
Variational quantum eigensolver (VQE) is an efficient classical-quantum
hybrid method to take advantage of quantum computers in the Noisy
Intermediate-Scale Quantum (NISQ) era. In this work we test the performance of
VQE by studying the $J_1$-$J_2$ anti-ferromagnetic Heisenberg model on the
kagome lattice, which is found to display a first order phase transition at
$J_2 / J_1 \approx 0.01$. By comparing the VQE states with the exact
diagonalization results, we find VQE energies agree well with the exact values
in most region of parameters for the 18-site system we studied. However, near
the phase transition point, VQE tends to converge to the excited states when
the number of variational parameters is not large enough. For the system
studied in this work, this issue can be solved by either increasing the number
of parameters or by initializing the parameters with converged values for
$J_2/J_1$ away from the phase transition point. Our results provide useful
guidance for the practical application of VQE on real quantum computers to
study strongly correlated quantum many-body systems.
Magnetic materials with highly anisotropic chemical bonding can be exfoliated
to realize ultrathin sheets or interfaces with highly controllable optical or
spintronics responses, while also promising novel cross-correlation phenomena
between electric polarization and the magnetic texture. The vast majority of
these van-der-Waals magnets are collinear ferro-, ferri-, or antiferromagnets,
with a particular scarcity of lattice-incommensurate helimagnets of defined
left- or right-handed rotation sense, or helicity. Here we use polarized
neutron scattering to reveal cycloidal, or conical, magnetic structures in
DyTe$_3$, where insulating double-slabs of dysprosium square nets are separated
by highly metallic tellurium layers. We identify a hierarchy of energy scales
with -- in order of decreasing strength -- antiferromagnetic exchange
interactions, magnetocrystalline anisotropy, and periodic modulations of the
exchange energy. The latter are attributed to magneto-elastic coupling to the
unconventional charge order in DyTe$_3$. This easily cleavable metallic
helimagnet also hosts a complex magnetic phase diagram indicative of competing
interactions. Our work paves the way for twistronics research, where
helimagnetic layers can be combined to form complex spin textures on-demand,
using the vast family of rare earth chalcogenides and beyond.
In the quantum anomalous Hall (QAH) effect, chiral edge states are present in
the absence of magnetic fields due to the intrinsic band topology. In this
work, we predict that a synthesized two-dimensional metal-organic material, a
Fe(biphenolate)$_3$ network, can be a unique QAH insulator, in which there are
three consecutive nontrivial bandgaps. Based on first-principles calculations
with effective model analysis, we reveal such nontrivial topology is from the
$3$d$_{xz}$ and $3$d$_{yz}$ orbitals of Fe atoms. Moreover, we further study
the effect of substrates, and the results shows that the metallic substrates
used in the experiments (Ag and Cu) are unfavorable for observing the QAH
effect whereas a hexagonal boron nitride substrate with a large bandgap may be
a good candidate, where the three consecutive QAH gaps appear inside the
substrate gap. The presence of three consecutive bandgaps near the Fermi level
will significantly facilitate observations of the QAH effect in experiments.
In this study, we discovered that the energy gap above the vacuum level in
the projected bulk band structure of Ag(100) prevents electrons in the
first-order field emission resonance (FER) from inducing the surface plasmons.
This mechanism allows light emission from FER to reveal characteristics of
triplet states and Auger-type excitation resulting from two-electron tunneling
in FER. According to optical spectra, surface plasmons can be induced by
electrons in the zeroth-order FER. However, corresponding radiative decay can
also trigger Auger-type excitation, whose energy state is influenced by the
sharpness-dependent image potential acting on the scanning tunneling microscope
tip.
The pairing symmetry of superconducting states is a critical topic in the
realm of topological superconductivity. However, the pairing symmetry of the
$\mathrm{AV_3Sb_5}$ family, wherein $\mathrm{A=K,Rb,Cs}$, remains
indeterminate. To address this issue, we formulate an effective model on the
kagome lattice to describe topological superconducting states featuring chiral
charge density wave. Through this model, we explore the topological phase
diagrams and thermal Hall conductivity under various parameters, with and
without spin-orbit coupling. Our analysis reveals that the disparities in
thermal Hall conductivity curves between different pairing symmetries are
safeguarded by the topology resulting from the interplay of spin-orbital
coupling and superconducting states. Remarkably, this theoretical prediction
can potentially enable the differentiation of various superconducting pairing
symmetries in materials via experimental measurements of thermal Hall
conductivity curves.
Two-dimensional (2D) honeycomb ferromagnets, such as monolayer
chromium-trihalides, are predicted to behave as topological magnon insulators -
characterized by an insulating bulk and topologically protected edge states,
giving rise to a thermal magnon Hall effect. Here we report the behavior of the
topological magnons in monolayer CrI$_3$ under external stimuli, including
biaxial and uniaxial strain, electric gating, as well as in-plane and
out-of-plane magnetic field, revealing that one can thereby tailor the magnetic
states as well as the size and the topology of the magnonic bandgap. These
findings broaden the perspective of using 2D magnetic materials to design
topological magnonic devices.
Twisted bilayer graphene (TBG) is a recently discovered two-dimensional
superlattice structure which exhibits strongly-correlated quantum many-body
physics, including strange metallic behavior and unconventional
superconductivity. Most of TBG exotic properties are connected to the emergence
of a pair of isolated and topological flat electronic bands at the so-called
magic angle, $\theta \approx 1.05^{\circ}$, which are nevertheless very
fragile. In this work, we show that, by employing chiral optical cavities, the
topological flat bands can be stabilized away from the magic angle in an
interval of approximately $0.8^{\circ}<\theta<1.3^{\circ}$. As highlighted by a
simplified theoretical model, time reversal symmetry breaking, induced by the
chiral nature of the cavity, plays a fundamental role in flattening the
isolated bands and gapping out the rest of the spectrum. The efficiency of the
cavity is discussed as a function of the twisting angle, the light-matter
coupling and the optical cavity characteristic frequency. Our results
demonstrate the possibility of engineering flat bands in TBG using optical
devices, extending the onset of strongly-correlated topological electronic
phases in Moir\'e superlattices to a wider range in the twisting angle.
We model the influence of an in-plane magnetic field on the orbital motion of
electrons in rhombohedral graphene multilayers. For zero field, the low-energy
band structure includes a pair of flat bands near zero energy which are
localized on the surface layers of a finite thin film. For finite field, we
find that the zero-energy bands persist and that level bifurcations occur at
energies determined by the component of the in-plane wave vector $q$ that is
parallel to the external field. The occurrence of level bifurcations is
explained by invoking semiclassical quantization of the zero field Fermi
surface of rhombohedral graphite. We find parameter regions with a single
isoenergetic contour of Berry phase zero corresponding to a conventional Landau
level spectrum and regions with two isoenergetic contours, each of Berry phase
$\pi$, corresponding to a Dirac-like spectrum of levels. We write down an
analogous one-dimensional tight-binding model and relate the persistence of the
zero-energy bands in large magnetic fields to a soliton texture supporting
zero-energy states in the Su-Schreiffer-Heeger model. We show that different
states contributing to the zero-energy flat bands in rhombohedral graphene
multilayers in a large field, as determined by the wave vector $q$, are
localized on different bulk layers of the system, not just the surfaces.
We propose an invasion model where domains grow up to their convex hulls and
merge when they overlap. This model can be seen as a continuum and isotropic
counterpart of bootstrap percolation models. From numerical investigations of
the model starting with randomly scattered discs in two dimensions, we find an
invasion transition that occurs via macroscopic avalanches. The disc
concentration threshold and the sharpness of the transition are found to
decrease as the system size is increased. Our results are consistent with a
vanishing threshold in the limit of infinitely large system sizes. However this
limit could not be investigated by simulations. For finite initial
concentrations of discs, the cluster size distribution presents a power-law
tail characterized by an exponent that varies approximately linearly with the
initial concentration of discs. These results at finite initial concentration
open novel directions for the understanding of the transition in systems of
finite size. Furthermore, we find that the domain area distribution has
oscillations with discontinuities. In addition, the deviation from circularity
of large domains is constant. Finally, we compare our results to experimental
observations on de-adhesion of graphene induced by the intercalation of
nanoparticles.
Active processes drive and guide biological dynamics across scales -- from
subcellular cytoskeletal remodelling, through tissue development in
embryogenesis, to population-level bacterial colonies expansion. In each of
these, biological functionality requires collective flows to occur while
self-organized structures are protected; however, the mechanisms by which
active flows can spontaneously constrain their dynamics to preserve structure
have not previously been explained. By studying collective flows and defect
dynamics in active nematic films, we demonstrate the existence of a
self-constraint -- a two-way, spontaneously arising relationship between
activity-driven isosurfaces of flow boundaries and mesoscale nematic
structures. Our results show that self-motile defects are tightly constrained
to viscometric surfaces -- contours along which vorticity and strain-rate
balance. This in turn reveals that self-motile defects break mirror symmetry
when they move along a single viscometric surface, in contrast with
expectations. This is explained by an interdependence between viscometric
surfaces and bend walls -- elongated narrow kinks in the orientation field.
Although we focus on extensile nematic films, numerical results show the
constraint holds whenever activity leads to motile half-charge defects. This
mesoscale cross-field self-constraint offers a new framework for tackling
complex 3D active turbulence, designing dynamic control into biomimetic
materials, and understanding how biological systems can employ active stress
for dynamic self-organization.
I propose monoradical nanographenes without C3 symmetry as building blocks to
design two-dimensional (2D) carbon crystals. As representative examples I study
the honeycomb and Kagome lattices, showing that by replacing the sites with
olympicene radicals the band dispersion near the Fermi energy corresponds,
respectively, to that of Kekul\'e/anti-Kekul\'e graphene and breathing Kagome
tight-binding models. As a consequence, finite islands of these new crystals
present corner states close to the Fermi energy, just like the parent models.
In the case of Kekul\'e/anti-Kekul\'e graphene, such states are topologically
protected, standing as examples of second-order topological insulators with a
non-zero Z2- or Z6-Berry phase. Differently, those of the breathing Kagome
lattice are of trivial nature, but the ground state has been predicted to be a
spin liquid in the antiferromagnetic Heisenberg model. Hence, 2D systems made
of low-symmetric nanographenes may be convenient platforms to explore exotic
physics in carbon materials.
Electroluminescence, a non-thermal radiative process, is ubiquitous in
semi-conductors and insulators but fundamentally precluded in metals. We show
here that this restriction can be circumvented in high-quality graphene. By
investigating the radiative emission of semi-metallic graphene field-effect
transistors over a broad spectral range, spanning the near- and mid-infrared,
we demonstrate direct far-field electroluminescence from hBN-encapsulated
graphene in the mid-infrared under large bias in ambient conditions. Through a
series of test experiments ruling out its incandescence origin, we determine
that the electroluminescent signal results from the electrical pumping produced
by interband tunneling. We show that the mid-infrared electroluminescence is
spectrally shaped by a natural quarter-wave resonance of the heterostructure.
This work invites a reassessment of the use of metals and semi-metals as
non-equilibrium light emitters, and the exploration of their intriguing
specificities in terms of carrier injection and relaxation, as well as emission
tunability and switching speed.
A monolayer of $MoS_{2}$ has a non-centrosymmetric crystal structure, with
spin polarized bands. It is a two valley semiconductor with direct gap falling
in the visible range of the electromagnetic spectrum. Its optical properties
are of particular interest in relation to valleytronics and possible device
applications. We study the longitudinal and the transverse Hall dynamical
conductivity which is decomposed into charge, spin and valley contributions.
Circular polarized light associated with each of the two valleys separately is
considered and results are filtered according to spin polarization. Temperature
can greatly change the spin admixture seen in the frequency window where they
are not closely in balance.
The topological Hall effect (THE) originates from the real-space Berry phase
that an electron gains when its spin follows the spatially varying non-trivial
magnetization textures, such as skyrmions. Such topologically protected
magnetization textures can provide great potential for information storage and
processing. Since directly imaging the skyrmions or detecting the magnetic
diffraction of skyrmion lattice are significantly more challenging than
conducting Hall measurements, THE has been widely used to attest the presence
of skyrmions. However, the key feature of THE, namely the bump/dip in the Hall
signal is not sufficient proof of THE. Here, we use empirical numerical
modeling to demonstrate all possible THE-like signals that two anomalous Hall
effect (AHE) signals with opposite signs can superpose. Besides the
reproduction of many published results by the numerical model, we propose an
exotic {\lq THE\rq} could, in principle, emerge with finely tuned two-channel
AHE. The importance of the scrupulous re-examination of the THE observed in
experiments cannot be exaggerated.
Unpaired Majorana zero-modes are central to topological quantum computation
schemes as building blocks of topological qubits, and are therefore under
intense experimental and theoretical investigation. Their generalizations to
parafermions and Fibonacci anyons are also of great interest, in particular for
universal quantum computation schemes. In this work, we find a different
generalization of Majorana zero-modes in effectively non-interacting systems,
which are zero-energy bound states that exhibit a cross structure -- two
straight, perpendicular lines in the complex plane -- composed of the complex
number entries of the zero-mode wavefunction on a lattice, rather than a single
straight line formed by complex number entries of the wavefunction on a lattice
as in the case of an unpaired Majorana zero-mode. These cross zero-modes are
realized for topological skyrmion phases under certain open boundary conditions
when their characteristic momentum-space spin textures trap topological
defects. They therefore serve as a second type of bulk-boundary correspondence
for the topological skyrmion phases. In the process of characterizing this
defect bulk-boundary correspondence, we develop recipes for constructing
physically-relevant model Hamiltonians for topological skyrmion phases,
efficient methods for computing the skyrmion number, and introduce
three-dimensional topological skyrmion phases into the literature.
The fractional quantum Hall effect was experimentally discovered in 1982. It
was observed that the Hall conductivity $\sigma_{yx}$ of a two-dimensional
electron system is quantized, $\sigma_{yx}=e^2/3h$, in the vicinity of the
Landau level filling factor $\nu=1/3$. In 1983, Laughlin proposed a many-body
variational wave function, which he claimed described a ``new state of matter''
-- a homogeneous incompressible liquid with fractionally charged
quasi-particles. Here I develop an exact diagonalization theory that makes it
possible to calculate the energy and other physical properties of the ground
and excited states of a system of $N$ two-dimensional Coulomb interacting
electrons in a strong magnetic field and in the field of a compensating
positively charged background. The only assumption of the theory is that all
electrons are assumed to be in the lowest Landau level. I present results for
$N\le 7$ and show that the true ground state resembles a sliding Wigner
crystal. I also calculate the physical properties of the $\nu=1/3$ Laughlin
state for $N\le 8$ and show that properties of the ``Laughlin liquid'' are
quantitatively and qualitatively different from those of the true ground state.
In addition, I show that the variational principle that was used for the
estimate of the Laughlin state energy in the thermodynamic limit does not work
in this limit, since one can specify an infinitely large number of different
trial wave functions giving the same variational energy at $N\to\infty$. I also
show that some physical properties of the Laughlin liquid contradict
fundamental physical principles.
The generalized quantum double lattice realization of 2d topological orders
based on Hopf algebras is discussed in this work. Both left-module and
right-module constructions are investigated. The ribbon operators and the
classification of topological excitations based on the representations of the
quantum double of Hopf algebras are discussed. To generalize the model to a 2d
surface with boundaries and surface defects, we present a systematic
construction of the boundary Hamiltonian and domain wall Hamiltonian. The
algebraic data behind the gapped boundary and domain wall are comodule algebras
and bicomodule algebras. The topological excitations in the boundary and domain
wall are classified by bimodules over these algebras. The ribbon operator
realization of boundary-bulk duality is also discussed. Finally, via the Hopf
tensor network representation of the quantum many-body states, we solve the
ground state of the model in the presence of the boundary and domain wall.
We present a theoretical study of how a spatially-varying quasiparticle
velocity in honeycomb lattices, achievable using strained graphene or in
engineered cold-atom optical lattices that have a spatial dependence to the
local tunneling amplitude, can yield the Rindler Hamiltonian embodying an
observer accelerating in Minkowski spacetime. Within this setup, a sudden
switch-on of the spatially-varying tunneling (or strain) yields a spontaneous
production of electron-hole pairs, an analogue version of the Unruh effect
characterized by the Unruh temperature. We discuss how this thermal behavior,
along with Takagi's statistics inversion, can manifest themselves in
photo-emission and scanning tunneling microscopy experiments. We also calculate
the average electronic conductivity and find that it grows linearly with
frequency $\omega$. Finally, we find that the total system energy at zero
environment temperature looks like Planck's blackbody result for photons due to
the aforementioned statistics inversion, whereas for an initial thermally
excited state of fermions, the total internal energy undergoes stimulated
particle reduction.
Classical artificial neural networks have witnessed widespread successes in
machine-learning applications. Here, we propose fermion neural networks (FNNs)
whose physical properties, such as local density of states or conditional
conductance, serve as outputs, once the inputs are incorporated as an initial
layer. Comparable to back-propagation, we establish an efficient optimization,
which entitles FNNs to competitive performance on challenging machine-learning
benchmarks. FNNs also directly apply to quantum systems, including hard ones
with interactions, and offer in-situ analysis without preprocessing or
presumption. Following machine learning, FNNs precisely determine topological
phases and emergent charge orders. Their quantum nature also brings various
advantages: quantum correlation entitles more general network connectivity and
insight into the vanishing gradient problem, quantum entanglement opens up
novel avenues for interpretable machine learning, etc.
We investigate the vibrational properties of topologically disordered
materials by analytically studying particles that harmonically oscillate around
random positions. Exploiting classical field theory in the thermodynamic limit
at $T=0$, we build up a self-consistent model by analyzing the Hessian
utilizing Euclidean Random Matrix theory. In accordance with earlier findings
[T. S. Grigera et al.J.~Stat.~Mech.~11 (2011) P02015.], we take non-planar
diagrams into account to correctly address multiple local scattering events. By
doing so, we end up with a first principles theory that can predict the main
anomalies of athermal disordered materials, including the boson peak, sound
softening, and Rayleigh damping of sound. In the vibrational density of states,
the sound modes lead to Debye's law for small frequencies. Additionally, an
excess appears in the density of states starting as $\omega^4$ in the low
frequency limit, which is attributed to (quasi-) localized modes.
We study symmetry-protected topological (SPT) phase transitions induced by
stacking two gapped one-dimensional subsystems in BDI symmetry class. The
topological invariant of the entire system is a sum of three topological
invariants: two from each subsystem and an emerging topological invariant from
the stacking. We find that any symmetry-preserving stacking of topologically
trivial subsystems can drive the entire system into a topologically nontrivial
phase. We explain this intriguing SPT phase transitions by conditions set by
orbital degrees of freedom and time-reversal symmetry. To exemplify the SPT
transition, we provide a concrete model which consists of an atomic chain and a
spinful nanowire with spin-orbit interaction and $s$-wave superconducting
order. The stacking-induced SPT transition drives this heterostructure into a
zero-field topological superconducting phase.
A general analysis of line defect renormalisation group (RG) flows in the
$\varepsilon$ expansion below $d=4$ dimensions is undertaken. The defect beta
function for general scalar-fermion bulk theories is computed to
next-to-leading order in the bulk couplings. Scalar models as well as
scalar-fermion models with various global symmetries in the bulk are considered
at leading non-trivial order. Different types of potential infrared (IR) defect
conformal field theories (dCFTs) and their RG stability are discussed. The
possibility of multiple IR stable dCFTs is realised in specific examples with
hypertetrahedral symmetry in the bulk. The one-point function coefficient of
the order parameter in the stable IR dCFT of the cubic model is computed at
next-to-leading order and compared with that in the IR dCFT of the Heisenberg
model.
It was recently discovered that friction between surfaces bearing
phosphatidylcholine (PC) lipid bilayers can be increased by two orders of
magnitude or more via an externally-applied electric field, and that this
increase is fully reversible when the field is switched off. While this
striking effect holds promising application potential, its molecular origin
remains unknown due to difficulty in experimentally probing confined membrane
structure at a molecular level. Our earlier molecular dynamics simulations
revealed the equilibrium electroporated structure of such confined lipid
membranes under an electric field; here we extend this approach to study the
associated sliding friction between two solid surfaces across such PC bilayers.
We identify the enhanced friction in the field as arising from membrane
undulations due to the electroporation; this leads to some dehydration at the
lipid-water interfaces, leading to closer contact and thus increased attraction
between the zwitterionic headgroups, which results in increased frictional
dissipation between the bilayers as they slide past each other. Additionally,
the electric field facilitates formation of lipid bridges spanning the
intersurface gap; at the sliding velocities of the experiments, these bridges
increase the friction by topologically-forcing the slip-plane to pass through
the acyl tail-tail interface, associated with higher dissipation during
sliding. Our results account quantitatively for the experimentally-observed
electro-modulated friction with boundary lipid bilayers, and indicate more
generally how they may affect interactions between contacting surfaces, where
high local transverse fields may be ubiquitous.
Hexagonal boron nitride (hBN), having an in-plane hexagonal structure in the
sp2 arrangement of atoms, proclaims structural similarity with graphene with
only a small lattice mismatch. Despite having nearly identical atomic
arrangements and exhibiting almost identical properties, the electronic
structures of the two materials are fundamentally different. Considering the
aforementioned context, a new hybrid material with enhanced properties can be
evolved combining both materials. This experiment involves liquid phase
exfoliation of hBN and two-dimensional nanocomposites of GO-hBN with varying
hBN and graphene oxide (GO) ratios. The optical and vibrational studies
conducted using UV-Vis absorption and Raman spectroscopic analysis report the
tuning of electron-phonon interaction (EPI) in the GO-hBN nanocomposite as a
function of GO content (%). This interaction depends on disorder-induced
electronic and vibrational modifications addressed by Urbach energy (Eu) and
asymmetry parameter (q), respectively. The EPI contribution to the induced
disorders estimated from UV-Vis absorption spectra is represented as EPI
strength (Ee-p) and its impact observed in Raman phonon modes is quantified as
an asymmetry parameter (q). The inverse of the asymmetry parameter is related
to Ee-p, as Ee-p ~ 1/|q|. Here in this article, a linear relationship has been
established between Eu and the proportional parameter (k), where k is
determined as the ratio of the intensity of specific Raman mode (I) and q2,
explaining the disorders' effect on Raman line shape. Thus a correlation
between Urbach energy and the asymmetry parameter of Raman mode confirms the
tuning of EPI with GO content (%) in GO-hBN nanocomposite.

Date of feed: Fri, 09 Jun 2023 00:30:00 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]+) **Anderson Critical Metal Phase in Trivial States Protected by $C_{2z}T$ Symmetry on Average. (arXiv:2306.04683v1 [cond-mat.dis-nn])**

Fa-Jie Wang, Zhen-Yu Xiao, Raquel Queiroz, B. Andrei Bernevig, Ady Stern, Zhi-Da Song

**Intrinsic antiferromagnetic multimeronic N\'eel spin-textures in ultrathin films. (arXiv:2306.04720v1 [cond-mat.mtrl-sci])**

Amal Aldarawsheh, Moritz Sallermann, Muayad Abusaa, Samir Lounis

**Automatic graph representation algorithm for heterogeneous catalysis. (arXiv:2306.04742v1 [cond-mat.mtrl-sci])**

Zachary Gariepy, ZhiWen Chen, Isaac Tamblyn, Chandra Veer Singh, Conrard Giresse Tetsassi Feugmo

**The Performance of VQE across a phase transition point in the $J_1$-$J_2$ model on kagome lattice. (arXiv:2306.04851v1 [cond-mat.str-el])**

Yuheng Guo, Mingpu Qin

**Non-coplanar helimagnetism in the layered van-der-Waals metal DyTe$_3$. (arXiv:2306.04854v1 [cond-mat.mtrl-sci])**

Shun Akatsuka, Sebastian Esser, Shang Gao, Seno Aji, Yoshichika Onuki, Taka-hisa Arima, Taro Nakajima, Max Hirschberger

**Three consecutive quantum anomalous Hall gaps in a metal-organic network. (arXiv:2306.04912v1 [cond-mat.str-el])**

Xiang-Long Yu, Tengfei Cao, Rui Wang, Ya-Min Quan, Jiansheng Wu

**Triplet State and Auger-Type Excitation Originating from Two-Electron Tunneling in Field Emission Resonance on Ag(100). (arXiv:2306.04916v1 [cond-mat.mes-hall])**

Shin-Ming Lu, Ho-Hsiang Chang, Wei-Bin Su, Wen-Yuan Chan, Kung-Hsuan Lin, Chia-Seng Chang

**Topological Superconducting States and Quasiparticle Transport on Kagome Lattice. (arXiv:2306.05034v1 [cond-mat.supr-con])**

Zi-Qian Zhou, Weimin Wang, Zhi Wang, Dao-Xin Yao

**Tunable magnon topology in monolayer CrI$_\mathbf{3}$ under external stimuli. (arXiv:2306.05104v1 [cond-mat.mes-hall])**

M. Soenen, M. V. Milosevic

**Engineering flat bands in twisted-bilayer graphene away from the magic angle with chiral optical cavities. (arXiv:2306.05149v1 [cond-mat.mes-hall])**

Cunyuan Jiang, Matteo Baggioli, Qing-Dong Jiang

**Solitons induced by an in-plane magnetic field in rhombohedral multilayer graphene. (arXiv:2306.05237v1 [cond-mat.mes-hall])**

Max Tymczyszyn, Peter H. Cross, Edward McCann

**Domain convexification: a simple model for invasion processes. (arXiv:2306.05273v1 [cond-mat.stat-mech])**

David Martin-Calle, Olivier Pierre-Louis

**Spontaneous Self-Constraint in Active Nematic Flows. (arXiv:2306.05328v1 [cond-mat.soft])**

Louise C. Head, Claire Dore, Ryan Keogh, Lasse Bonn, Amin Doostmohammadi, Kristian Thijssen, Teresa Lopez-Leon, Tyler N. Shendruk

**Olympicene radicals as building blocks of two-dimensional anisotropic networks. (arXiv:2306.05346v1 [cond-mat.mes-hall])**

Ricardo Ortiz

**Electroluminescence of the graphene 2D semi-metal. (arXiv:2306.05351v1 [cond-mat.mes-hall])**

A. Schmitt, L. Abou-Hamdan, M. Tharrault, S. Rossetti, D. Mele, R. Bretel, A. Pierret, M. Rosticher, P. Morfin, T. Taniguchi, K. Watanabe, J.M. Berroir, G. Fève, G. Ménard, B. Plaçais, C. Voisin, J.P. Hugonin, J.J. Greffet, P. Bouchon, Y. De Wilde, E. Baudin

**Longitudinal and spin/valley Hall optical conductivity in single layer $MoS_{2}$. (arXiv:1211.3094v2 [cond-mat.mes-hall] UPDATED)**

Zhou Li, J. P. Carbotte

**Overheated Topological Hall Effect. (arXiv:1812.09847v7 [cond-mat.mtrl-sci] UPDATED)**

Liang Wu, Yujun Zhang

**Defect bulk-boundary correspondence of topological skyrmion phases of matter. (arXiv:2206.02251v2 [cond-mat.mes-hall] UPDATED)**

Shu-Wei Liu, Li-kun Shi, Ashley M. Cook

**Toward a correct theory of the fractional quantum Hall effect: What is the ground state of a quantum Hall system at $\nu=1/3$?. (arXiv:2206.05152v4 [cond-mat.mes-hall] UPDATED)**

S. A. Mikhailov

**Boundary and domain wall theories of 2d generalized quantum double model. (arXiv:2207.03970v5 [quant-ph] UPDATED)**

Zhian Jia, Dagomir Kaszlikowski, Sheng Tan

**Unruh Effect and Takagi's Statistics Inversion in Strained Graphene. (arXiv:2209.08053v3 [cond-mat.mes-hall] UPDATED)**

Anshuman Bhardwaj, Daniel E. Sheehy

**A fermion neural network with efficient optimization and quantum applicability. (arXiv:2211.05793v2 [quant-ph] UPDATED)**

Pei-Lin Zheng, Jia-Bao Wang, Yi Zhang

**Vibrational phenomena in glasses at low temperatures captured by field theory of disordered harmonic oscillators. (arXiv:2211.10891v2 [cond-mat.dis-nn] UPDATED)**

Florian Vogel, Matthias Fuchs

**Stacking-Induced Symmetry-Protected Topological Phase Transitions. (arXiv:2302.07633v2 [cond-mat.mes-hall] UPDATED)**

Sang-Jun Choi, Björn Trauzettel

**Line Defect RG Flows in the $\varepsilon$ Expansion. (arXiv:2302.14069v3 [hep-th] UPDATED)**

William H. Pannell, Andreas Stergiou

**Tuning friction via topologically electro-convoluted lipid-membrane boundary layers. (arXiv:2303.08555v3 [cond-mat.soft] UPDATED)**

Di Jin, Jacob Klein

**Tuning the electron-phonon interaction via exploring the interrelation between Urbach energy and Fano-type asymmetric Raman line shape in GO-hBN nanocomposites. (arXiv:2305.01362v3 [cond-mat.mtrl-sci] UPDATED)**

Vidyotma Yadav, Tanuja mohanty

Found 4 papers in prb We investigate the interaction between surface acoustic waves (SAWs) and spin waves (SWs) in a Pt/Co($2\phantom{\rule{0.16em}{0ex}}\mathrm{nm}$)/Ru($0.85\phantom{\rule{0.16em}{0ex}}\mathrm{nm}$)/Co($2\phantom{\rule{0.16em}{0ex}}\mathrm{nm}$)/Pt compensated synthetic antiferromagnet (SAF) composed of… We show that in contrast to the conventional view of a mean-field Landau-type behavior, the oxygen octahedral tilt $(R)$ and polarization $(P)$ in the ${A}_{3}{B}_{2}{\mathrm{O}}_{7}$ Ruddlesden-Popper hybrid improper ferroelectric ${(\mathrm{Ca},\mathrm{Sr})}_{3}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$ e… We report a study of the noncentrosymmetric TaReSi superconductor by means of the muon-spin rotation and relaxation $(μ\mathrm{SR})$ technique, complemented by electronic band-structure calculations. Its superconductivity, with ${T}_{c}=5.5\phantom{\rule{0.28em}{0ex}}\text{K}$ and upper critical fie… Perfect absorbers, which can achieve total absorption of all incoming energy, have been extensively studied in the last decades for various important technologies in general wave systems. Here, we show that perfect absorption (PA) is generically associated with topological spectral phase singularity…

Date of feed: Fri, 09 Jun 2023 03:17:05 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+) **Nonreciprocal transmission of magnetoacoustic waves in compensated synthetic antiferromagnets**

M. Küß, M. Hassan, Y. Kunz, A. Hörner, M. Weiler, and M. Albrecht

Author(s): M. Küß, M. Hassan, Y. Kunz, A. Hörner, M. Weiler, and M. Albrecht

[Phys. Rev. B 107, 214412] Published Thu Jun 08, 2023

**Scaling behavior of order parameters for the hybrid improper ferroelectric ${(\mathrm{Ca},\mathrm{Sr})}_{3}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$**

Jing Kong, Alicia Manjón-Sanz, Jue Liu, Frederick Marlton, Tsz Wing Lo, Dangyuan Lei, Mads Ry Vogel Jørgensen, and Abhijit Pramanick

Author(s): Jing Kong, Alicia Manjón-Sanz, Jue Liu, Frederick Marlton, Tsz Wing Lo, Dangyuan Lei, Mads Ry Vogel Jørgensen, and Abhijit Pramanick

[Phys. Rev. B 107, 224103] Published Thu Jun 08, 2023

**Fully gapped superconductivity and topological aspects of the noncentrosymmetric superconductor TaReSi**

T. Shang, J. Z. Zhao, Lun-Hui Hu, D. J. Gawryluk, X. Y. Zhu, H. Zhang, J. Meng, Z. X. Zhen, B. C. Yu, Z. Zhou, Y. Xu, Q. F. Zhan, E. Pomjakushina, and T. Shiroka

Author(s): T. Shang, J. Z. Zhao, Lun-Hui Hu, D. J. Gawryluk, X. Y. Zhu, H. Zhang, J. Meng, Z. X. Zhen, B. C. Yu, Z. Zhou, Y. Xu, Q. F. Zhan, E. Pomjakushina, and T. Shiroka

[Phys. Rev. B 107, 224504] Published Thu Jun 08, 2023

**Spectral phase singularity and topological behavior in perfect absorption**

Mengqi Liu, Weijin Chen, Guangwei Hu, Shanhui Fan, Demetrios N. Christodoulides, Changying Zhao, and Cheng-Wei Qiu

Author(s): Mengqi Liu, Weijin Chen, Guangwei Hu, Shanhui Fan, Demetrios N. Christodoulides, Changying Zhao, and Cheng-Wei Qiu

[Phys. Rev. B 107, L241403] Published Thu Jun 08, 2023

Found 1 papers in nano-lett

Date of feed: Thu, 8 Jun 2023 15:13:55 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]+) **[ASAP] Twisted Bilayer Graphene Induced by Intercalation**

Bixuan Li, Juntian Wei, Chunqiao Jin, Kunpeng Si, Lingjia Meng, Xingguo Wang, Yangyu Jia, Qianqian He, Peng Zhang, Jinliang Wang, and Yongji GongNano LettersDOI: 10.1021/acs.nanolett.3c00560

Found 1 papers in science-adv

Date of feed: Wed, 07 Jun 2023 19:03:57 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]+) **In-plane anisotropy of graphene by strong interlayer interactions with van der Waals epitaxially grown MoO3**

Hangyel Kim, Jong Hun Kim, Jungcheol Kim, Jejune Park, Kwanghee Park, Ji-Hwan Baek, June-Chul Shin, Hyeongseok Lee, Jangyup Son, Sunmin Ryu, Young-Woo Son, Hyeonsik Cheong, Gwan-Hyoung Lee

Science Advances, Volume 9, Issue 23, June 2023.