Found 29 papers in cond-mat The recent claim of room temperature superconductivity in a copper-doped lead
apatite compound, called LK-99, has sparked remarkable interest and
controversy. Subsequent experiments have largely failed to reproduce the
claimed superconductivity, while theoretical works have identified multiple key
features including strong electronic correlation, structural instabilities, and
dopability constraints. A puzzling claim of several recent theoretical studies
is that both parent and copper-doped lead apatite structures are dynamically
unstable at the harmonic level, questioning decades of experimental reports of
the parent compound structures and the recently proposed copper-doped
structures. In this work, we demonstrate that both parent and copper-doped lead
apatite structures are dynamically stable at room temperature. Anharmonic
phonon-phonon interactions play a key role in stabilizing some copper-doped
phases, while most phases are largely stable even at the harmonic level. We
also show that dynamical stability depends on both volume and correlation
strength, suggesting controllable ways of exploring the copper-doped lead
apatite structural phase diagram. Our results fully reconcile the theoretical
description of the structures of both parent and copper-doped lead apatite with
experiment.
Recent scanning tunneling microscopy (STM) measurements have observed a
multi-peak energy structure on the positive bias side in dilute-hole-doped
cuprates, where tightly-bound hole pairs are identified as the building blocks
that can continuously persist into the superconducting regime. In this work, we
study the single-particle spectral function based on a two-hole ground state
wavefunction [Phys. Rev. X 12, 011062 (2022)], which can provide a consistent
understanding of the experimental results. Here the wavefunction structure with
a dichotomy of $d$-wave Cooper pairing and $s$-wave ``twisted hole'' pairing
will lead to two branches in the local spectral function where the low-lying
one corresponds to a conventional nodal quasiparticle, and a higher energy
branch is associated with a ``twisted'' quasiparticle above the pair breaking
or ``pseudogap'' energy. These energies can be further extended into energy
spectra in the momentum space, in which the low-energy dispersion agrees
excellently with the Quantum Monte Carlo numerical result. The implications for
the STM spectra in the superconducting state will also be discussed.
Current proposals for topological quantum computation (TQC) based on Majorana
zero modes (MZM) have mostly been focused on coupled-wire architecture which
can be challenging to implement experimentally. To explore alternative building
blocks of TQC, in this work we study the possibility of obtaining robust MZM at
the corners of triangular superconducting islands, which often appear
spontaneously in epitaxial growth. We first show that a minimal three-site
triangle model of spinless $p$-wave superconductor allows MZM to appear at
different pairs of vertices controlled by a staggered vector potential, which
may be realized using coupled quantum dots and can already demonstrate
braiding. For systems with less fine-tuned parameters, we suggest an
alternative structure of a "hollow" triangle subject to uniform supercurrents
or vector potentials, in which MZM generally appear when two of the edges are
in a different topological phase from the third. We also discuss the
feasibility of constructing the triangles using existing candidate MZM systems
and of braiding more MZM in networks of such triangles.
We study the appearance of topological Floquet flat bands in
alternating-twist multilayer graphene (ATMG) which has an alternating relative
twist angle $\pm\theta$ near the first magic angle. While the system hosts both
flat bands and a steep Dirac cone in the static case, the circularly polarized
laser beam can open a gap at the Moir\'{e} $K$ point and create Floquet flat
bands carrying non-zero Chern numbers. Considering the recent
lattice-relaxation results, we find that the topological flat band is
well-isolated for the effective interlayer tunneling in $n=3, 4, 5$ layer. Such
dynamically produced topological flat bands are potentially observed in the
experiment and thus provide a feasible way to realize the fractional Chern
insulator.
A local criterion of topological phase transitions is established based on
the Morse theory: a topological phase transition occurs when the count of Morse
critical points of the order function changes. The locations in space where
this change occurs are referred to as spatial critical points of the
topological phase transition. In cases of continuous topological phase
transitions, these spatial critical points are identified through the emergence
of degenerate Morse critical points, where local maxima and minima of the order
function split or merge. This resembles the formation and annihilation of a
particle-antiparticle pair. The wide-ranging applicability of this criterion is
demonstrated through three case studies that explore topological phase
transitions in both configuration space and reciprocal space. Every topological
phase transition is linked to a localized physical process that cannot be
comprehended solely by studying changes in a global quantity, such as a
topological invariant.
We study states with intrinsic topological order subjected to local
decoherence from the perspective of separability, i.e., whether a decohered
mixed state can be expressed as an ensemble of short-range entangled pure
states. We focus on toric codes and the X-cube fracton state and provide
evidence for the existence of decoherence-induced separability transitions that
precisely coincide with the error-recovery transitions. A key insight is that
local decoherence acting on the 'parent' cluster states of these models results
in a Gibbs state.
We investigate the second R\'enyi entropy of two intervals in the massless
Thirring model describing a self-interacting Dirac fermion in two dimensions.
Boson-fermion duality relating this model to a free compact boson theory
enables us to simplify the calculation of the second R\'enyi entropy, reducing
it to the evaluation of the partition functions of the bosonic theory on a
torus. We derive exact results on the second R\'enyi entropy, and examine the
dependence on the sizes of the intervals and the coupling constant of the model
both analytically and numerically. We also explore the mutual R\'enyi
information, a measure quantifying the correlation between the two intervals,
and find that it generally increases as the coupling constant of the Thirring
model becomes larger.
We show that all lowest Landau level projected and unprojected chiral parton
type fractional quantum Hall ground and edge state trial wave functions, which
take the form of products of integer quantum Hall wave functions, can be
expressed as conformal field theory (CFT) correlation functions, where we can
associate a chiral algebra to each state which defines a CFT that is the
``smallest'' such CFT that can generate the corresponding ground and edge state
trial wave functions. A field-theoretic generalisation of Laughlin's plasma
analogy, known as generalised screening, is formulated for these states. If
this holds, along with an additional assumption, we argue that the inner
products of edge state trial wave functions, for parton states with a unique
densest wave function, can be expressed as matrix elements of an exponentiated
local action operator of the CFT, generalising the result of Dubail et al. [PRB
85, 11531 (2012)], which implies the equality between edge state and
entanglement level counting to state counting in the CFT. We numerically test
this result in the case of the unprojected $\nu = 2/5$ composite fermion state
and the bosonic $\nu = 1$ $\phi_2^2$ parton state. We discuss how Read's
arguments [PRB 79, 045308 (2009)] still apply, implying that conformal blocks
of the CFT defined by the given chiral algebra are valid quasi-hole trial wave
functions, with the adiabatic braiding statistics given by the monodromy of
these functions. It is shown that all chiral composite fermion wave functions
can be expressed as CFT correlation functions without explicit symmetrisation
and that the ground, edge, and quasi-hole trial wave functions of the
$\phi_n^m$ parton states can be expressed as the conformal blocks of the $U(1)
\otimes SU(n)_m$ WZW models. We discuss the $\phi_2^k$ series in detail, where
several examples of quasi-hole braiding statistics calculations are given.
This letter investigates low frequency 1/ f noise in hBN encapsulated
graphene device in a dual gated geometry. The noise study is performed as a
function of top gate carrier density (nT G) at different back gate densities
(nBG). The noise at low nBG is found to be independent of top gate carrier
density. With increasing nBG, noise value increases and a noise peak is
observed near charge inhomogeneity of the device. Further increase in nBG leads
to decrease in noise magnitude. The shape of the noise is found to be closely
related to charge inhomogeneity region of the device. Moreover, the noise and
conductivity data near charge neutrality shows clear evidence of noise
emanating from combination of charge number and mobility fluctuation
We study the effect of a local potential shift induced by a side electrode on
the edge modes at the boundary between gapped and ungapped bilayer graphene. A
potential shift close to the gapped-ungapped boundary causes the emergence of
unprotected edge modes, propagating in both directions along the boundary.
These counterpropagating edge modes allow edge backscattering, as opposed to
the case of valley-momentum-locked edge modes. We then calculate the
conductance of a bilayer graphene wire in presence of finger-gate electrodes,
finding strong asymmetries with energy inversion and deviations from
conductance quantization that can be understood with the gate-induced
unprotected edge modes.
The high-pressure behavior of monoclinic VO$_2$ is revisited by a combination
of Raman spectroscopy and X-ray diffraction on a single crystal under
hydrostatic conditions at room temperature. A soft mode is observed up to P$_c$
= 13.9(1) GPa. At this pressure, an isostructural phase transition between two
monoclinic phases M$_1$ and M$_1$' hinders this instability. The features of
this transformation (no apparent volume jump) indicate that the compression at
ambient temperature passes close to a critical point. An analysis based on the
Landau theory of phase transitions gives a complete description of the P-T
phase diagram. The M1' is characterized by spontaneous displacements of the
oxygen sub-lattice without any strong modification of the VV dimers distances
nor the twist angle of vanadium chains. The spontaneous displacements of oxygen
and the spontaneous deformations of the ($b_{M1}$, $c_{M1}$) plane follow the
same quadratic dependence with pressure and scales with spontaneous shifts of
the Raman phonons located at 225, 260 and 310 cm$^{-1}$. Pressure-induced
shifts of the Raman peaks allows for new assignment of several Raman modes. In
particular, the A$_g$(1)+B$_g$(1) modes at 145 cm$^{-1}$ are identified as the
vanadium displacive phonons. A second transformation in the metallic phase X,
which is found triclinic (P$\bar1$) is observed starting at 32 GPa, with a wide
coexistence region (up to 42 GPa). Upon decompression, phase X transforms,
between 20 GPa and 3 GPa, to another phase that is neither the M$_1$' nor M$_1$
phase. The structural transitions identified under pressure match with all the
previously reported electronic modifications confirming that lattice and
electronic degrees of freedom are closely coupled in this correlated material.
We investigate the finite-time behavior of pair production from the vacuum by
a time-dependent Sauter pulsed electric field using the spinor quantum
electrodynamics (QED). In the adiabatic basis, the one-particle distribution
function in momentum space is determined by utilizing the exact analytical
solution of the Dirac equation. By examining the temporal behavior of the
one-particle distribution function and the momentum spectrum of created pairs
in the sub-critical field limit $(E_0 = 0.2E_c)$, we observe oscillatory
patterns in the longitudinal momentum spectrum(LMS) of particles at finite
times. These oscillations arise due to quantum interference effects resulting
from the dynamical tunneling. Furthermore, we derive an approximate and
simplified analytical expression for the distribution function at finite times,
which allows us to explain the origin and behavior of these oscillations.
Additionally, we discuss the role of the vacuum polarization function and its
counter term to the oscillations in LMS vacuum excitation. We also analyse the
transverse momentum spectrum (TMS).
The formation of persistent charge currents in mesoscopic systems remains an
interesting and actual topic of condensed matter research. Here, we analyze the
formation of spontaneous arising persistent currents of charged fermions in
2-dimensional electron-hole ribbons on the top and bottom of a 3-dimensional
topological insulator. In such a device the two-dimensional Dirac fermions with
opposite chiralities are spatially separated that allows these currents to flow
in the opposite directions without compensating each other. The nature of this
phenomenon is based on the interference of the quasiparticle quantum waves
which are scattered with asymmetric scattering phases at the lateral n-p chiral
junction and then reflected back by the external boundaries of the ribbon. As a
result quasiparticles in the ribbon are shown to be in unified electron-hole
quantum states carrying the persistent current.
Ultracold atoms in optical lattices have emerged as powerful quantum
simulators of translationally invariant systems with many applications in e.g.
strongly-correlated and topological systems. However, the ability to locally
tune all Hamiltonian parameters remains an outstanding goal that would enable
the simulation of a wider range of quantum phenomena. Motivated by recent
advances in quantum gas microscopes and optical tweezers, we here show
theoretically how local control over individual tunnelling links in an optical
lattice can be achieved by incorporating local time-periodic potentials. We
propose to periodically modulate the on-site energy of individual lattice sites
and employ Floquet theory to demonstrate how this can result in full individual
control over the tunnelling amplitudes in one dimension. We provide various
example configurations realising interesting topological models such as
extended Su-Schrieffer-Heeger models that would be challenging to realize by
other means. Extending to two dimensions, we present that local periodic
driving in a three-site plaquette allows for full simultaneous control over the
relative tunnelling amplitudes and the gauge-invariant flux piercing the
plaquette, providing a clear stepping stone in building a fully programmable 2D
tight-binding model. This local modulation scheme is applicable to many
different lattice geometries.
Nonmagnetic impurity scattering is known to shift up the Ginzburg-Landau
parameter $\kappa$ of a superconductor. In this case, when the system is
initially in type I, it can change its magnetic response, crossing the
intertype domain with $\kappa \sim 1$ between the two standard
superconductivity types and arriving at type II. In the present work we
demonstrate that the impact of disorder can be much more profound in the
presence of the multiband structure of the charge carrier states. In
particular, when the band diffusivities differ from each other, the intertype
domain tends to expand significantly, including points with $\kappa \gg 1$ that
belong to deep type-II in conventional single-band superconductors. Our finding
sheds light on the nontrivial disorder effect and significantly complements
earlier results on the enlargement of the intertype domain in clean multiband
superconductors.
We show that, for each symmetry class based on the tenfold way
classification, the effective Dirac operator obtained by integrating out the
additional bulk direction takes a value in the corresponding classifying space,
from which we obtain the flat band Hamiltonian. We then obtain the overlap
Dirac operator for each symmetry class and establish the Ginsparg--Wilson
relation associated with $\mathcal{C}$ and $\mathcal{T}$ symmetries, and also
the mod-two index theorem.
Silicon hole quantum dots have been the subject of considerable attention
thanks to their strong spin-orbit coupling enabling electrical control. The
physics of silicon holes is qualitatively different from germanium holes and
requires a separate theoretical description. In this work, we theoretically
study the electrical control and coherence properties of silicon hole dots with
different magnetic field orientations. We discuss possible experimental
configurations to optimize the electric dipole spin resonance (EDSR) Rabi time,
the phonon relaxation time, and the dephasing due to random telegraph noise.
Our main findings are: (i) The in-plane $g$-factor is strongly influenced by
the presence of the split-off band, as well as by any shear strain. The
$g$-factor is a non-monotonic function of the top gate electric field, in
agreement with recent experiments. This enables coherence sweet spots at
specific values of the top gate field and specific magnetic field orientations.
(ii) Even a small ellipticity (aspect ratios $\sim 1.2$) causes significant
anisotropy in the in-plane $g$-factor, which can vary by $50\% - 100\%$ as the
magnetic field is rotated in the plane. (iii) EDSR Rabi frequencies are
comparable to Ge, and the ratio between the relaxation time and the EDSR Rabi
time $\sim 10^5$. For an out-of-plane magnetic field the EDSR Rabi frequency is
anisotropic with respect to the orientation of the driving electric field,
varying by $\approx 20\%$ as the driving field is rotated in the plane. Our
work aims to stimulate experiments by providing guidelines on optimizing
configurations and geometries to achieve robust, fast and long-lived hole spin
qubits in silicon.
A new method is proposed to predict the topological properties of
one-dimensional periodic structures in wave physics, including quantum
mechanics. From Bloch waves, a unique complex valued function is constructed,
exhibiting poles and zeros. The sequence of poles and zeros of this function is
a topological invariant that can be linked to the Berry-Zak phase. Since the
characterization of the topological properties is done in the complex plane, it
can easily be extended to the case of non-hermitian systems. The sequence of
poles and zeros allows to predict topological phase transitions.
We propose a general principle of constructing non-Hermitian (NH) operators
for insulating and gapless topological phases in any dimension ($d$) that over
an extended NH parameter regime feature real eigenvalues and zero-energy
topological boundary modes, when in particular their Hermitian cousins are also
topological. However, the topological zero modes disappear when the NH
operators accommodate complex eigenvalues. These systems are always devoid of
NH skin effects, thereby extending the realm of the bulk-boundary
correspondence to NH systems in terms of solely the left or right zero-energy
boundary localized eigenmodes. We showcase these general and robust outcomes
for NH topological insulators in $d=1,2$ and $3$, encompassing their
higher-order incarnations, as well as for NH topological Dirac, Weyl and
nodal-loop semimetals. Possible realizations of proposed NH topological phases
in designer materials, optical lattices and classical metamaterials are
highlighted.
Majorana bound states constitute one of the simplest examples of emergent
non-Abelian excitations in condensed matter physics. A toy model proposed by
Kitaev shows that such states can arise at the ends of a spinless $p$-wave
superconducting chain. Practical proposals for its realization require coupling
neighboring quantum dots in a chain via both electron tunneling and crossed
Andreev reflection. While both processes have been observed in semiconducting
nanowires and carbon nanotubes, crossed-Andreev interaction was neither easily
tunable nor strong enough to induce coherent hybridization of dot states. Here
we demonstrate the simultaneous presence of all necessary ingredients for an
artificial Kitaev chain: two spin-polarized quantum dots in an InSb nanowire
strongly coupled by both elastic co-tunneling and crossed Andreev reflection.
We fine-tune this system to a sweet spot where a pair of Poor Man's Majorana
states is predicted to appear. At this sweet spot, the transport
characteristics satisfy the theoretical predictions for such a system,
including pairwise correlation, zero charge and stability against local
perturbations. While the simple system presented here can be scaled to simulate
a full Kitaev chain with an emergent topological order, it can also be used
imminently to explore relevant physics related to non-Abelian anyons.
A characteristic property of a gapless liquid state is its emergent symmetry
and dual symmetry, associated with the conservation laws of symmetry charges
and symmetry defects respectively. These conservation laws, considered on an
equal footing, can't be described simply by the representation theory of a
group (or a higher group). They are best described in terms of a topological
order (TO) with gappable boundary in one higher dimension; we call this the
symTO of the gapless state. The symTO can thus be considered a fingerprint of
the gapless state. We propose that a largely complete characterization of a
gapless state, up to local-low-energy equivalence, can be obtained in terms of
its maximal emergent symTO. In this paper, we review the
symmetry/topological-order (Symm/TO) correspondence and propose a precise
definition of maximal symTO. We discuss various examples to illustrate these
ideas. We find that the 1+1D Ising critical point has a maximal symTO described
by the 2+1D double-Ising topological order. We provide a derivation of this
result using symmetry twists in an exactly solvable model of the Ising critical
point. The critical point in the 3-state Potts model has a maximal symTO of
double (6,5)-minimal-model topological order. As an example of a noninvertible
symmetry in 1+1D, we study the possible gapless states of a Fibonacci anyon
chain with emergent double-Fibonacci symTO. We find the Fibonacci-anyon chain
without translation symmetry has a critical point with unbroken
double-Fibonacci symTO. In fact, such a critical theory has a maximal symTO of
double (5,4)-minimal-model topological order. We argue that, in the presence of
translation symmetry, the above critical point becomes a stable gapless phase
with no symmetric relevant operator.
We determine the Casimir energies and forces in a variety of potentially
experimentally viable setups, consisting of parallel plates made of perfect
electromagnetic conductors (PEMCs), which generalize perfect electric
conductors (PECs) and perfect magnetic conductors (PMCs), and Weyl semimetals
(WSMs). Where comparison is possible, our results agree with the Casimir forces
calculated elsewhere in the literature, albeit with different methods. We find
a multitude of known but also new cases where repulsive Casimir forces are in
principle possible, but restricting the setup to PECs combined with the
aforementioned WSM geometry, results in purely attractive Casimir forces.
We demonstrate that level crossings at the Fermi energy serve as robust
indicators for higher-order topology in two-dimensional superconductors of
symmetry class D. These crossings occur when the boundary condition in one
direction is continuously varied from periodic to open, revealing the
topological distinction between opposite edges. The associated Majorana numbers
acquire nontrivial values whenever the system supports two Majorana zero modes
distributed at its corners. Owing to their immunity to perturbations that break
crystalline symmetries, Fermi level crossings are able to characterize a wide
range of higher-order topological superconductors. By directly identifying the
level-crossing points from the bulk Hamiltonian, we establish the
correspondence between gapped bulk and Majorana corner states in higher-order
phases. In the end, we illustrate this correspondence using two toy models. Our
findings suggest that Fermi level crossings offer a possible avenue for
characterizing higher-order topological superconductors in a unifying
framework.
Exact solutions for non-Hermitian quantum many-body systems are rare but may
provide valuable insights into the interplay between Hermitian and
non-Hermitian components. We report our investigation of a non-Hermitian
variant of a p-wave Kitaev chain by introducing staggered imbalanced pair
creation and annihilation terms. We find that there exists a fixed line in the
phase diagram, at which the ground state remains unchanged in the presence of
non-Hermitian term under the periodic boundary condition for a finite system.
This allows the constancy of the topological index in the process of varying
the balance strength at arbitrary rate, exhibiting the robustness of the
topology for non-Hermitian Kitaev chain under time-dependent perturbations. The
underlying mechanism is investigated through the equivalent quantum spin system
obtained by the Jordan-Wigner transformation for infinite chain. In addition,
the exact solution shows that a resonant non-Hermitian impurity can induce a
pair of zero modes in the corresponding Majorana lattice, which asymptotically
approach the edge modes in the thermodynamic limit, manifesting the
bulk-boundary correspondence. Numerical simulation is performed for the quench
dynamics for the systems with slight deviation from the fixed line to show the
stability region in time. This work reveals the interplay between the pair
creation and annihilation pairing processes.
Optical micro-spectroscopy is an invaluable tool for studying and
characterizing samples ranging from classical semiconductors to low-dimensional
materials and heterostructures. To date, most implementations are based on
point-scanning techniques, which are flexible and reliable, but slow. Here, we
describe a setup for highly parallel acquisition of hyperspectral reflection
and photoluminescence microscope images using a push-broom technique. Spatial
as well as spectral distortions are characterized and their digital corrections
are presented. We demonstrate close-to diffraction-limited spatial imaging
performance and a spectral resolution limited by the spectrograph. The
capabilities of the setup are demonstrated by recording a hyperspectral
photoluminescence map of a CVD-grown MoSe$_2$-WSe$_2$ lateral heterostructure,
from which we extract the luminescence energies, intensities and peak widths
across the interface.
Understanding the origin of damping mechanisms in magnetization dynamics of
metallic ferromagnets is a fundamental problem for nonequilibrium many-body
physics of systems where quantum conduction electrons interact with localized
spins assumed to be governed by the classical Landau-Lifshitz-Gilbert (LLG)
equation. It is also of critical importance for applications, as damping
affects energy consumption and speed of spintronic and magnonic devices. Since
the 1970s, a variety of linear-response and scattering theory approaches have
been developed to produce widely used formulas for computation of
spatially-independent Gilbert scalar parameter as the magnitude of the Gilbert
damping term in the LLG equation. The largely unexploited for this purpose
Schwinger-Keldysh field theory (SKFT) offers additional possibilities, such as
to rigorously derive an extended LLG equation by integrating quantum electrons
out. Here we derive such equation whose Gilbert damping for metallic
ferromagnets is nonlocal, i.e., dependent on all localized spins at a given
time, and nonuniform, even if all localized spins are collinear and spin-orbit
coupling (SOC) is absent. This is in sharp contrast to standard lore, where
nonlocal damping is considered to emerge only if localized spins are
noncollinear; for such situations, direct comparison on the example of magnetic
domain wall shows that SKFT-derived nonlocal damping is an order of magnitude
larger than the previously considered one. Switching on SOC makes such nonlocal
damping anisotropic, in contrast to standard lore where SOC is usually
necessary to obtain nonzero Gilbert damping scalar parameter. Our analytical
formulas, with their nonlocality being more prominent in low spatial
dimensions, are fully corroborated by numerically exact quantum-classical
simulations.
Onsite gain-loss-induced topological braiding principle of non-Hermitian
energy bands is theoretically formulated in multiband lattice models with
Hermitian hopping amplitudes. Braid phase transition occurs when the gain-loss
parameter is tuned across exceptional point degeneracy. Laboratory realizable
effective-Hamiltonians are proposed to realize braid groups $\mathbb{B}_2$ and
$\mathbb{B}_3$ of two and three bands, respectively. While $\mathbb{B}_2$ is
trivially Abelian, the group $\mathbb{B}_3$ features non-Abelian braiding and
energy permutation originating from the collective behavior of multiple
exceptional points. Phase diagrams with respect to lattice parameters to
realize braid group generators and their non-commutativity are shown. The
proposed theory is conducive to synthesizing exceptional materials for
applications in topological computation and information processing.
We demonstrate terahertz chiral metamaterial cavities that break
time-reversal symmetry by coupling the degenerate linearly polarized modes of
two orthogonal sets of nano-antenna arrays using the inter-Landau level
transition of a two-dimensional electron gas in a perpendicular magnetic field,
realizing normalized light-matter coupling rates up to
$\Omega_R/\omega_{\mathrm{cav}} = 0.78$. The deep sub-wavelength confinement
and gap of the nano-antennas means that the ultra-strong coupling regime can be
reached even with a very small number of carriers, making it viable to be used
with a variety of 2D materials, including graphene. In addition it possesses a
non-degenerate chiral ground state that can be used to study the effect of
circularly polarized electromagnetic quantum fluctuations by means of
weakly-perturbing magneto-transport measurements.
The Z method is a popular atomistic simulation method for determining the
melting temperature where a sequence of molecular dynamics runs are carried out
to target the lowest system energy where the solid always melts. Homogeneous
melting at the limit of critical superheating, Th, is accompanied by a drop in
temperature as kinetic energy is converted to potential energy and the
equilibrium melting temperature, Tm, can be calculated directly from the liquid
state. Implementation of the Z method interfaced with modern ab initio
electronic structure packages use Hellmann-Feynman forces to propagate the ions
in the microcanonical(NVE) ensemble where the Mermin free energy plus the ionic
kinetic energy is conserved. The electronic temperature, Tel, is kept fixed
along the trajectory which may introduce some spurious ion-electron
interactions in MD runs with large temperature changes such as often seen in
homogeneous melting and freezing processes in the NVE ensemble. We estimate
systematic errors in the calculated melting temperature to choice of Tel for
two main mantle components, SiO2 and CaSiO3 at high pressure. Comparison of the
calculated melting temperature from runs where the Tel=Th and Tel=Tm
representing reasonable upper and lower boundaries respectively to choice of
Tel shows that the difference in melting temperature is 200-300 K for our two
test systems. The melting temperature decreases with increasing Tel due to the
increasing entropic stabilisation of the liquid and the systems melts typically
about 3 times faster in MD runs with Tel = Th compared to runs where Tel = Tm.
A careful choice of electron temperature in BOMD simulations where the ions are
propagated using Hellmann-Feynamn forces with the Mermin free energy + the
ionic kinetic energy being conserved is therefore essential for the critical
evaluation of the Z method and in particular at very high temperatures.

Date of feed: Fri, 22 Sep 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]+)|(flatband)|(flat.{1}band)|(LK.{1}99) **On the dynamical stability of copper-doped lead apatite. (arXiv:2309.11541v1 [cond-mat.supr-con])**

Sun-Woo Kim, Kang Wang, Siyu Chen, Lewis J. Conway, G. Lucian Pascut, Ion Errea, Chris J. Pickard, Bartomeu Monserrat

**Distinct quasiparticle excitations in single-particle spectral function. (arXiv:2309.11556v1 [cond-mat.str-el])**

Jing-Yu Zhao, Zheng-Yu Weng

**Superconducting triangular islands as a platform for manipulating Majorana zero modes. (arXiv:2309.11607v1 [cond-mat.mes-hall])**

Aidan Winblad, Hua Chen

**Topological Floquet Flat Bands in Irradiated Alternating Twist Multilayer Graphene. (arXiv:2309.11685v1 [cond-mat.mes-hall])**

Yingyi Huang

**A local criterion of topological phase transitions. (arXiv:2309.11738v1 [cond-mat.stat-mech])**

Yangfan Hu

**Separability transitions in topological states induced by local decoherence. (arXiv:2309.11879v1 [quant-ph])**

Yu-Hsueh Chen, Tarun Grover

**Entanglement R\'enyi entropy and boson-fermion duality in massless Thirring model. (arXiv:2309.11889v1 [hep-th])**

Harunobu Fujimura, Tatsuma Nishioka, Soichiro Shimamori

**Conformal field theory approach to parton fractional quantum Hall trial wave functions. (arXiv:2309.11910v1 [cond-mat.str-el])**

Greg J. Henderson, G. J. Sreejith, Steven H. Simon

**Origin of electrical noise near charge neutrality in dual gated graphene device. (arXiv:2309.12011v1 [cond-mat.mes-hall])**

Aaryan Mehra, Roshan Jesus Mathew, Chandan Kumar

**Electrostatic tuning of bilayer graphene edge modes. (arXiv:2309.12013v1 [cond-mat.mes-hall])**

Hira Ali, Llorenç Serra

**VO$_2$ under hydrostatic pressure: Isostructural phase transition close to a critical end-point. (arXiv:2309.12020v1 [cond-mat.str-el])**

P. Bouvier, L. Bussmann, D. Machon, I. Breslavetz, G. Garbarino, P. Strobel, V. Dmitriev

**Pair Production in time-dependent Electric field at Finite times. (arXiv:2309.12079v1 [hep-ph])**

Deepak, Manoranjan P. Singh

**Persistent current-carrying state of charge quasuparticles in $np$-ribbon featuring single Dirac cone. (arXiv:2309.12084v1 [cond-mat.mes-hall])**

Anatoly M. Kadigrobov, Ilya M. Eremin

**Individually tunable tunnelling coefficients in optical lattices using local periodic driving. (arXiv:2309.12124v1 [cond-mat.quant-gas])**

Georgia M. Nixon, F. Nur Unal, Ulrich Schneider

**Intertype superconductivity evoked by the interplay of disorder and multiple bands. (arXiv:2309.12133v1 [cond-mat.supr-con])**

P. M. Marychev, A. A. Shanenko, A. Vagov

**Band Flattening and Overlap Fermion. (arXiv:2309.12174v1 [hep-th])**

Taro Kimura, Masataka Watanabe

**Electrical operation of hole spin qubits in planar MOS silicon quantum dots. (arXiv:2309.12243v1 [cond-mat.mes-hall])**

Zhanning Wang, Abhikbrata Sarkar, S. D. Liles, Andre Saraiva, A. S. Dzurak, A. R. Hamilton, Dimitrie Culcer

**Characterizing the topological properties of one-dimensional non-hermitian systems without the Berry-Zak phase. (arXiv:2309.12280v1 [quant-ph])**

Didier Felbacq, Emmanuel Rousseau

**Model non-Hermitian topological operators without skin effect. (arXiv:2309.12310v1 [cond-mat.mes-hall])**

Daniel J. Salib, Sanjib Kumar Das, Bitan Roy

**Realization of a minimal Kitaev chain in coupled quantum dots. (arXiv:2206.08045v2 [cond-mat.mes-hall] UPDATED)**

Tom Dvir, Guanzhong Wang, Nick van Loo, Chun-Xiao Liu, Grzegorz P. Mazur, Alberto Bordin, Sebastiaan L. D. ten Haaf, Ji-Yin Wang, David van Driel, Francesco Zatelli, Xiang Li, Filip K. Malinowski, Sasa Gazibegovic, Ghada Badawy, Erik P. A. M. Bakkers, Michael Wimmer, Leo P. Kouwenhoven

**Emergent generalized symmetry and maximal symmetry-topological-order. (arXiv:2212.14432v2 [cond-mat.str-el] UPDATED)**

Arkya Chatterjee, Wenjie Ji, Xiao-Gang Wen

**Interplay between chiral media and perfect electromagnetic conductor plates: repulsive vs. attractive Casimir force transitions. (arXiv:2301.12870v6 [hep-th] UPDATED)**

Thomas Oosthuyse, David Dudal

**Higher-order topological superconductors characterized by Fermi level crossings. (arXiv:2303.07698v4 [cond-mat.mes-hall] UPDATED)**

Hong Wang, Xiaoyu Zhu

**Fixed lines in a non-Hermitian Kitaev chain with spatially balanced pairing processes. (arXiv:2305.00496v2 [quant-ph] UPDATED)**

Y. B. Shi, Z. Song

**Hyperspectral photoluminescence and reflectance microscopy of 2D materials. (arXiv:2305.06945v2 [physics.optics] UPDATED)**

David Tebbe (1), Marc Schütte (2), Baisali Kundu (3), Bernd Beschoten (1 and 4), Prasana K. Sahoo (3), Lutz Waldecker (1) ((1) 2nd Institute of Physics and JARA-FIT, RWTH Aachen University, Aachen, Germany, (2) 2nd Institute of Physics, RWTH Aachen University, Aachen, Germany, (3) Materials Science Center, Indian Institute of Technology, Kharagpur, West Bengal, India, (4) JARA-FIT Institute for Quantum Information, Forschungszentrum Jülich GmbH and RWTH Aachen University, Aachen, Germany)

**Gilbert damping in metallic ferromagnets from Schwinger-Keldysh field theory: Intrinsically nonlocal and nonuniform, and made anisotropic by spin-orbit coupling. (arXiv:2306.13013v2 [cond-mat.mes-hall] UPDATED)**

Felipe Reyes-Osorio, Branislav K. Nikolic

**Gain-loss-induced non-Abelian Bloch braids. (arXiv:2306.13056v2 [quant-ph] UPDATED)**

B. Midya

**Terahertz chiral metamaterial cavities breaking time-reversal symmetry. (arXiv:2308.03195v2 [cond-mat.mes-hall] UPDATED)**

Johan Andberger, Lorenzo Graziotto, Luca Sacchi, Mattias Beck, Giacomo Scalari, Jérôme Faist

**Influence of electronic entropy on Hellmann-Feynman forces in ab initio molecular dynamics with large temperature changes. (arXiv:2308.03963v2 [cond-mat.mtrl-sci] UPDATED)**

Ming Geng, Chris E. Mohn

Found 11 papers in prb Dynamical quantum phase transitions occur in dynamically evolving quantum systems when nonanalyticities occur at critical times in the return rate, a dynamical analog of the free energy. This extension of the concept of phase transitions can be brought into contact with another, namely, that of topo… Recently, nonlocal spatial mirror symmetry breaking metasurfaces have been proposed to generate spatiotemporal optical vortices (STOVs), which carry transverse orbital angular momenta. Here, we investigate the topological property of the STOV generator and show that spatial mirror symmetry breaking … A new mechanism leading to a switchable We show that a two-body Jastrow wave function is able to capture the ground-state properties of the $S=1$ Heisenberg chain with nearest-neighbor superexchange $J$ and single-ion anisotropy term $D$, in both the topological and large-$D$ phases (with $D/J≥0$). Here, the optimized Jastrow pseudopotent… We have experimentally studied the Landau levels near the quantum limit in the magnetic Dirac material ($\mathrm{Eu},\mathrm{Gd}){\mathrm{MnBi}}_{2}$. In this series of materials, the Fermi level is systematically controlled by substituting ${\mathrm{Eu}}^{2+}$ with ${\mathrm{Gd}}^{3+}$ while keepin… Symmetry-protected topological (SPT) phases exhibit nontrivial short-ranged entanglement protected by symmetry and cannot be adiabatically connected to trivial product states while preserving the symmetry. In contrast, intrinsic topological phases do not need ordinary symmetry to stabilize them and … In this study, we conducted a numerical investigation on the Hall conductance (${σ}_{\mathrm{Hall}}$) of graphene based on the magnetic energy band structure calculated using a nonperturbative magnetic-field-containing relativistic tight-binding approximation (MFRTB) method. The nonperturbative MFRT… Interfacial coupling between graphene and other two-dimensional materials can give rise to intriguing physical phenomena. In particular, several theoretical studies predict that the interplay between graphene and an antiferromagnetic insulator could lead to the emergence of quantum anomalous Hall ph… Moiré materials have risen to the forefront of physics research because of their ability to realize a disparate set of fascinating physical phenomena in these systems. Besides interesting electronic properties, the moiré pattern has been suggested to be used as a magnifying glass for local strain an… We introduce a model of Dirac fermions in $2+1$ dimensions with a semimetallic, a quantum spin-Hall insulating (QSHI), and an $s$-wave superconducting (SSC) phase. The phase diagram features a multicritical point at which all three phases meet as well as a QSHI-SSC deconfined critical point. The QSH… We investigate electronic states in a two-dimensional network consisting of interacting quantum wires, a model adopted for twisted bilayer systems. We construct general operators which describe various scattering processes in the system. In a twisted bilayer structure, the moiré periodicity allows f…

Date of feed: Fri, 22 Sep 2023 03:17:20 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) **Dynamical bulk-boundary correspondence and dynamical quantum phase transitions in higher-order topological insulators**

T. Masłowski and N. Sedlmayr

Author(s): T. Masłowski and N. Sedlmayr

[Phys. Rev. B 108, 094306] Published Thu Sep 21, 2023

**Topologically protected generation of spatiotemporal optical vortices with nonlocal spatial mirror symmetry breaking metasurface**

Junyi Huang, Hongliang Zhang, Bingjun Wu, Tengfeng Zhu, and Zhichao Ruan

Author(s): Junyi Huang, Hongliang Zhang, Bingjun Wu, Tengfeng Zhu, and Zhichao Ruan

[Phys. Rev. B 108, 104106] Published Thu Sep 21, 2023

**Landau-Ginzburg-Devonshire theory of the chiral phase transition in ${180}^{∘}$ domain walls of ${\mathrm{PbTiO}}_{3}$**

I. Rychetsky, W. Schranz, and A. Tröster

Author(s): I. Rychetsky, W. Schranz, and A. Tröster*Bloch*-type polarization in a domain wall separating two ferroelectric domain states is proposed. A biquadratic coupling of the primary order parameter and its gradient originating from inhomogeneous electrostriction triggers the chiral phase transition (*Ising*-…

[Phys. Rev. B 108, 104107] Published Thu Sep 21, 2023

**Jastrow wave function for the spin-1 Heisenberg chain: The string order revealed by the mapping to the classical Coulomb gas**

Davide Piccioni, Christian Apostoli, Federico Becca, Guglielmo Mazzola, Alberto Parola, Sandro Sorella, and Giuseppe E. Santoro

Author(s): Davide Piccioni, Christian Apostoli, Federico Becca, Guglielmo Mazzola, Alberto Parola, Sandro Sorella, and Giuseppe E. Santoro

[Phys. Rev. B 108, 104417] Published Thu Sep 21, 2023

**Variation of Landau level splitting in the Fermi level controlled Dirac metals $(\mathrm{Eu},\mathrm{Gd}){\mathrm{MnBi}}_{2}$**

H. Sakai, K. Nakagawa, K. Tsuruda, J. Shiogai, K. Akiba, M. Tokunaga, S. Kimura, S. Awaji, A. Tsukazaki, H. Murakawa, and N. Hanasaki

Author(s): H. Sakai, K. Nakagawa, K. Tsuruda, J. Shiogai, K. Akiba, M. Tokunaga, S. Kimura, S. Awaji, A. Tsukazaki, H. Murakawa, and N. Hanasaki

[Phys. Rev. B 108, 115142] Published Thu Sep 21, 2023

**Symmetry-enriched topological order from partially gauging symmetry-protected topologically ordered states assisted by measurements**

Yabo Li (李雅博), Hiroki Sukeno (助野裕紀), Aswin Parayil Mana, Hendrik Poulsen Nautrup, and Tzu-Chieh Wei (魏子傑)

Author(s): Yabo Li (李雅博), Hiroki Sukeno (助野裕紀), Aswin Parayil Mana, Hendrik Poulsen Nautrup, and Tzu-Chieh Wei (魏子傑)

[Phys. Rev. B 108, 115144] Published Thu Sep 21, 2023

**Quantized Hall conductance in graphene by nonperturbative magnetic-field-containing relativistic tight-binding approximation method**

Md. Abdur Rashid, Masahiko Higuchi, and Katsuhiko Higuchi

Author(s): Md. Abdur Rashid, Masahiko Higuchi, and Katsuhiko Higuchi

[Phys. Rev. B 108, 125132] Published Thu Sep 21, 2023

**Exploring the interfacial coupling between graphene and the antiferromagnetic insulator ${\mathrm{MnPSe}}_{3}$**

Xin Yi, Qiao Chen, Kexin Wang, Yuanyang Yu, Yi Yan, Xin Jiang, Chengyu Yan, and Shun Wang

Author(s): Xin Yi, Qiao Chen, Kexin Wang, Yuanyang Yu, Yi Yan, Xin Jiang, Chengyu Yan, and Shun Wang

[Phys. Rev. B 108, 125427] Published Thu Sep 21, 2023

**Creating a custom-designed moiré magnifying glass to probe local atomic lattice rotations in twisted bilayer graphene**

Chen-Yue Hao, Jia-Qi He, Huai-Jia Qiao, Yi-Wen Liu, Ya-Ning Ren, and Lin He

Author(s): Chen-Yue Hao, Jia-Qi He, Huai-Jia Qiao, Yi-Wen Liu, Ya-Ning Ren, and Lin He

[Phys. Rev. B 108, 125429] Published Thu Sep 21, 2023

**Simulation of fermionic and bosonic critical points with emergent SO(5) symmetry**

Toshihiro Sato, Zhenjiu Wang, Yuhai Liu, Disha Hou, Martin Hohenadler, Wenan Guo, and Fakher F. Assaad

Author(s): Toshihiro Sato, Zhenjiu Wang, Yuhai Liu, Disha Hou, Martin Hohenadler, Wenan Guo, and Fakher F. Assaad

[Phys. Rev. B 108, L121111] Published Thu Sep 21, 2023

**General scattering and electronic states in a quantum-wire network of moiré systems**

Chen-Hsuan Hsu, Daniel Loss, and Jelena Klinovaja

Author(s): Chen-Hsuan Hsu, Daniel Loss, and Jelena Klinovaja

[Phys. Rev. B 108, L121409] Published Thu Sep 21, 2023

Found 2 papers in nat-comm **Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+)|(flatband)|(flat.{1}band)|(LK.{1}99) **Kapitza-resistance-like exciton dynamics in atomically flat MoSe2-WSe2 lateral heterojunction**

< author missing >

**Strained few-layer MoS2 with atomic copper and selectively exposed in-plane sulfur vacancies for CO2 hydrogenation to methanol**

< author missing >