Found 28 papers in cond-mat Stakeholders representing concerns of national and global leadership,
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Honeycomb layered frameworks with metallophilic bilayers have garnered
traction in various disciplines due to their unique configuration and numerous
physicochemical and topological properties, such as fast ionic conduction,
coordination chemistry, and structural defects. These properties make them
attractive for energy storage applications, leading to increased attention
towards their metallophilic bilayer arrangements. This Review focuses on recent
advancements in this field, including characterisation techniques like X-ray
absorption spectroscopy and high-resolution transmission electron microscopy,
particularly for silver-based oxides. It also highlights strategies related to
cationic-deficient phases induced by topology or temperature, expanding the
compositional space of honeycomb layered frameworks with a focus on cationic
bilayer architectures. The Review further discusses theoretical approaches for
understanding the bilayered structure, especially concerning critical phenomena
at the monolayer-bilayer phase transition. Honeycomb layered frameworks are
described as optimised lattices within the congruent sphere packing problem,
equivalent to a specific two-dimensional conformal field theory. The
monolayer-bilayer phase transition involves a 2D-to-3D crossover. Overall, this
Review aims to provide a panoramic view of honeycomb layered frameworks with
metallophilic bilayers and their potential applications in the emerging field
of quantum matter. It is valuable for recent graduates and experts alike across
diverse fields, extending beyond materials science and chemistry.
Two-dimensional time-reversal-invariant topological superconductors host
helical Majorana fermions at their boundary. We study the fate of these edge
states under the combined influence of strong interactions and disorder, using
the effective 1D lattice model for the edge introduced by Jones and Metlitski
[Phys. Rev. B 104, 245130 (2021)]. We specifically develop a strong-disorder
renormalization group analysis of the lattice model and identify a regime in
which time-reversal is broken spontaneously, creating random magnetic domains;
Majorana fermions localize to domain walls and form an infinite-randomness
fixed point, identical to that appearing in the random transverse-field Ising
model. While this infinite-randomness fixed point describes a fine-tuned
critical point in a purely 1D system, in our edge context there is no obvious
time-reversal-preserving perturbation that destabilizes the fixed point. Our
analysis thus suggests that the infinite-randomness fixed point emerges as a
stable phase on the edge of 2D topological superconductors when strong disorder
and interactions are present.
Twisted bilayer graphene near the magic angle is known to have a cascade of
insulating phases at integer filling factors of the low-energy bands. In this
Letter we address the nature of these phases through an unrestricted,
self-consistent Hartree-Fock calculation on the lattice that accounts for
\emph{all} electronic bands. Using numerically unbiased methods, we show that
Coulomb interactions screened only by metallic gates produce ferromagnetic
insulating states at integer fillings $\nu\in[-4,4]$ with maximal spin
polarization $M_{\text{FM}}=4-|\nu|$. With the exception of the $\nu=0,-2$
states, all other integer fillings have insulating phases with additional
sublattice symmetry breaking and antiferromagnetism in the \emph{remote} bands.
Valley polarization is found away from half filling. Odd filling factors
$|\nu|=1,3$ have anomalous quantum Hall states with Chern number
$|\mathcal{C}|=1$, whereas the $|\nu|=3$ states show strong particle-hole
\emph{asymmetry} in the small-gap regime. We map the metal-insulator
transitions of these phases as a function of the background dielectric
constant.
Phyllosilicates emerge as a promising class of large bandgap lamellar
insulators. Their applications have been explored from fabrication of
graphene-based devices to 2D heterostructures based on transition metal
dicalcogenides with enhanced optical and polaritonics properties. In this
review, we provide an overview on the use of IR s-SNOM for studying nano-optics
and local chemistry of a variety of 2D natural phyllosilicates. Finally, we
bring a brief update on applications that combine natural lamellar minerals
into multifunctional nanophotonic devices driven by electrical control.
A recently emerging concept for quantum phase discovery is the controlled
gapping of linear band crossings in topological semimetals. For example,
achieving topological superconducting and charge-density-wave (CDW) gapping
could introduce Majorana zero modes and axion electrodynamics, respectively.
Light engineering of correlation gaps in topological materials provides a new
avenue of achieving exotic topological phases inaccessible by conventional
tuning methods such as doping and straining. Here we demonstrate a light
control of correlation gaps and ultrafast phase switchings in a model CDW and
polaron insulator (TaSe$_4$)$_2$I recently predicted to be an axion insulator.
Our ultrafast terahertz photocurrent spectroscopy reveals a two-step,
non-thermal melting of polarons and electronic CDW gap via studying the fluence
dependence of a {\em longitudinal} circular photogalvanic current. The
helicity-dependent photocurrent observed along the propagation of light reveals
continuous ultrafast switchings from the polaronic state, to the CDW (axion)
phase, and finally to a hidden Weyl phase as the pump fluence increases. Other
distinguishing features corroborating with the light-induced switchings
include: mode-selective coupling of coherent phonons to polaron and CDW
modulation, and the emergence of a {\em non-thermal} chiral photocurrent above
pump threshold of CDW-related phonons. The ultrafast chirality control of
correlated topological states revealed here is important to realize axion
electrodynamics and quantum computing.
Introducing quasiparticle anisotropy in graphene via uniaxial strain has a
profound effect on the polarization charge density induced by external
impurities, both Coulomb and short-range. In particular the charge distribution
induced by a Coulomb impurity exhibits a power law tail modulated by a
strain-dependent admixture of angular harmonics. The appearance of distributed
charge is in sharp contrast to the response in pristine/isotropic graphene,
where for subcritical impurities the polarization charge is fully localized at
the impurity position. It is also interesting to note that our results are
obtained strictly at zero chemical potential, and the behavior is fundamentally
distinct from the typical Friedel oscillations observed at finite chemical
potential. For weak to moderate strain, the $d$-wave symmetry is dominant. The
presence of Dirac cone tilt, relevant to some 2D materials beyond graphene, can
also substantially affect the induced charge distribution. Finally we consider
impurities with short range potentials, and study the effect of strain on the
charge response. Our results were obtained in the continuum via perturbation
theory valid for weak (subcritical) potentials, and supported by numerical
lattice simulations based on density functional theory.
We investigate the role of pressure, via its Hessian tensor $\mathbf{H}$, on
amplification of vorticity and strain-rate and contrast it with other inviscid
nonlinear mechanisms. Results are obtained from direct numerical simulations of
isotropic turbulence with Taylor-scale Reynolds number in the range $140-1300$.
Decomposing $\mathbf{H}$ into local isotropic ($\mathbf{H}^{\rm I}$) and
nonlocal deviatoric ($\mathbf{H}^{\rm D}$) components reveals that
$\mathbf{H}^{\rm I}$ depletes vortex stretching (VS), whereas $\mathbf{H}^{\rm
D}$ enables it, with the former slightly stronger. The resulting inhibition is
significantly weaker than the nonlinear mechanism which always enables VS.
However, in regions of intense vorticity, identified using conditional
statistics, contribution from $\mathbf{H}$ dominates over nonlinearity, leading
to overall depletion of VS. We also observe near-perfect alignment between
vorticity and the eigenvector of $\mathbf{H}$ corresponding to the smallest
eigenvalue, which conforms with well-known vortex-tubes. We discuss the
connection between this depletion, essentially due to (local) $\mathbf{H}^{\rm
I}$, and recently identified self-attenuation mechanism [Buaria et al. {\em
Nat. Commun.} 11:5852 (2020)], whereby intense vorticity is locally attenuated
through inviscid effects. In contrast, the influence of $\mathbf{H}$ on
strain-amplification is weak. It opposes strain self-amplification, together
with VS, but its effect is much weaker than VS. Correspondingly, the
eigenvectors of strain and $\mathbf{H}$ do not exhibit any strong alignments.
For all results, the dependence on Reynolds number is very weak. In addition to
the fundamental insights, our work provides useful data and validation
benchmarks for future modeling endeavors, for instance in Lagrangian modeling
of velocity gradient dynamics, where conditional $\mathbf{H}$ is explicitly
modeled.
We focus on the transmission and reflection coefficients of light in systems
involving of topological insulators (TI). Due to the electro-magnetic coupling
in TIs, new mixing coefficients emerge leading to new components of the
electromagnetic fields of propagating waves. We have discovered a simple
heterostructure that provides a 100-fold enhancement of the mixing coefficients
for TI materials. Such effect increases with the TI's wave impedance. We also
predict a transverse deviation of the Poynting vector due to these mixed
coefficients contributing to the radiative electromagnetic field of an electric
dipole. Given an optimal configuration of the dipole-TI system, this deviation
could amount to $0.18\%$ of the Poynting vector due to emission near not
topological materials, making this effect detectable.
We examine the properties of topological strongly correlated superconductor
with bond disorder on triangular lattice and demonstrate that our theoretical
($t$-$J$-$U$) model exhibits some unique features of the Cu-doped apatite
$\mathrm{Pb_{10-\mathit{x}}Cu_\mathit{x}(PO_4)_{6}O}$. Namely, the paired state
appears only for carrier concentration $0.8 \lesssim x < 1$ and is followed by
a close-by phase separation into the superconducting and Mott insulating parts.
Furthermore, a moderate amount of the bond disorder ($\Delta t / t \lesssim 20
\%$) does not alter essentially the topology with robust Chern number $C=2$
which diminishes beyond that limit. A room-temperature superconductivity is
attainable only for the exchange to hopping ratio $J/|t| \ge 1$ if one takes
the bare bandwidth suggested by current DFT calculations. The admixture of
$s$-wave pairing component is induced by the disorder. The results have been
obtained within statistically consistent variational approximation (SGA).
We calculate the perpendicular electrical conductivity in twisted
three-dimensional graphite (rotationally-stacked graphite pieces) by using the
effective continuum model and the recursive Green's function method. In the low
twist angle regime $(\theta \lesssim 2^\circ)$, the conductivity shows a
non-monotonous dependence with a peak and dip structure as a function of the
twist angle. By analyzing the momentum-resolved conductance and the local
density of states, this behavior is attributed to the Fano resonance between
continuum states of bulk graphite and interface-localized states, which is a
remnant of the flat band in the magic-angle twisted bilayer graphene. We also
apply the formulation to the high-angle regime near the commensurate angle
$\theta \approx 21.8^\circ$, and reproduce the conductance peak observed in the
experiment.
We performed density functional theory (DFT)+$U$ and dynamical mean field
theory (DMFT) calculations with continuous time quantum Monte Carlo impurity
solver to investigate the electronic properties of V$_2$O$_5$ and
Li$_x$V$_2$O$_5$ ($x$ = 0.125 and 0.25). Pristine V$_2$O$_5$ is a
charge-transfer insulator with strong O $p$-V $d$ hybridization, and exhibits a
large band gap ($E_{\textrm{gap}}$) as well as non-zero conduction band (CB)
gap. We show that the band gap, the number of $d$ electrons of vanadium, $N_d$,
and conduction band (CB) gap for V$_2$O$_5$ obtained from our DMFT calculations
are in excellent agreement with the experimental values. While the DFT+$U$
approach replicates the experimental band gap, it overestimates the value of
$N_d$ and underestimates the CB gap. In the presence of low Li doping, the
electronic properties of V$_2$O$_5$ are mainly driven by a polaronic mechanism,
the electron spin resonance and electron nuclear double resonance
spectroscopies observed the coexistence of free and bound polarons. Notably,
our DMFT results identify both polaron types, with the bound polaron being
energetically preferred, while DFT+$U$ method predicts only the free polaron.
Our DMFT analysis also reveals that increased Li doping leads to electron
filling in the conduction band, shifting the Fermi level, this result
consistent with the observed Burstein-Moss shift upon enhanced Li doping and we
thus demonstrate that the DFT+DMFT approach can be used for accurate and
realistic description of strongly correlated materials.
We examine the aggregation behavior of AuNPs of different sizes on graphene
as function of temperature using molecular dynamic simulations with Reax Force
Field (ReaxFF). In addition, the consequences of such aggregation on the
morphology of AuNPs and the charge transfer behavior of AuNP-Graphene hybrid
structure are analyzed. The aggregation of AuNPs on graphene is confirmed from
the center of mass distance calculation. The simulation results indicate that
the size of AuNPs and temperature significantly affect the aggregation behavior
of AuNPs on graphene. The strain calculation showed that shape of AuNPs changes
due to the aggregation and the smaller size AuNPs on graphene exhibit more
shape changes than larger AuNPs at all the temperatures studies in this work.
The charge transfer calculation reveals that, the magnitude of charge transfer
is higher for larger AuNPs-graphene composite when compared with smaller
AuNPs-graphene composite. The charge transfer trend and the trends seen in the
number of Au atoms directly in touch with graphene are identical. Hence, our
results conclude that, quantity of Au atoms directly in contact with graphene
during aggregation is primarily facilitates charge transfer between AuNPs and
graphene.
Supramolecular chemistry protocols applied on surfaces offer compelling
avenues for atomic scale control over organic-inorganic interface structures.
In this approach, adsorbate-surface interactions and two-dimensional
confinement can lead to morphologies and properties that differ dramatically
from those achieved via conventional synthetic approaches. Here, we describe
the bottom-up, on-surface synthesis of one-dimensional coordination
nanostructures based on an iron (Fe)-terpyridine (tpy) interaction borrowed
from functional metal-organic complexes used in photovoltaic and catalytic
applications. Thermally activated diffusion of sequentially deposited ligands
and metal atoms, and intra-ligand conformational changes, lead to Fe-tpy
coordination and formation of these nanochains. Low-temperature Scanning
Tunneling Microscopy and Density Functional Theory were used to elucidate the
atomic-scale morphology of the system, providing evidence of a linear tri-Fe
linkage between facing, coplanar tpy groups. Scanning Tunneling Spectroscopy
reveals highest occupied orbitals with dominant contributions from states
located at the Fe node, and ligand states that mostly contribute to the lowest
unoccupied orbitals. This electronic structure yields potential for hosting
photo-induced metal-to-ligand charge transfer in the visible/near-infrared. The
formation of this unusual tpy/tri-Fe/tpy coordination motif has not been
observed for wet chemistry synthesis methods, and is mediated by the bottom-up
on-surface approach used here.
Broken time-reversal symmetry in the absence of spin order indicates the
presence of unusual phases such as orbital magnetism and loop currents. The
recently discovered family of kagome superconductors AV$_3$Sb$_5$ (A = K, Rb,
or Cs), hosting an exotic charge-density wave (CDW) state, has emerged as a
strong candidate for this phase. While initial experiments suggested that the
CDW phase breaks time-reversal symmetry, this idea is being intensely debated
due to conflicting experimental data. In this work we use laser-coupled
scanning tunneling microscopy (STM) to study RbV$_3$Sb$_5$. STM data shows that
the Fourier intensities of all three CDW peaks are different, implying that the
CDW breaks rotational and mirror symmetries. By applying linearly polarized
light along high-symmetry directions, we show that the relative intensities of
the CDW peaks can be reversibly switched, implying a substantial
electro-striction response, indicative of strong non-linear electron-phonon
coupling. A similar CDW intensity switching is observed with perpendicular
magnetic fields, which implies an unusual piezo-magnetic response that, in
turn, requires time-reversal symmetry-breaking. We show that the simplest CDW
that satisfies these constraints and reconciles previous seemingly
contradictory experimental data is an out-of-phase combination of bond charge
order and loop currents that we dub congruent CDW flux phase. Our laser-STM
data opens the door to the possibility of dynamic optical control of complex
quantum phenomenon in correlated materials.
Two-dimensional (2D) transition-metal dichalcogenides (TMDC) are considered
highly promising platforms for next-generation optoelectronic devices. Owing to
its atomically thin structure, device performance is strongly impacted by a
minute amount of defects. Although defects are usually considered to be
disturbing, defect engineering has become an important strategy to control and
design new properties of 2D materials. Here, we produce single S vacancies in a
monolayer of MoS$_2$ on Au(111). Using a combination of scanning tunneling and
atomic force microscopy, we show that these defects are negatively charged and
give rise to a Kondo resonance, revealing the presence of an unpaired electron
spin exchange coupled to the metal substrate. The strength of the exchange
coupling depends on the density of states at the Fermi level, which is
modulated by the moir\'e structure of the MoS$_2$ lattice and the Au(111)
substrate. In the absence of direct hybridization of MoS$_2$ with the metal
substrate, the S vacancy remains charge-neutral. Our results suggest that
defect engineering may be used to induce and tune magnetic properties of
otherwise non-magnetic materials.
Percolation has two mean-field theories, the Gaussian fixed point (GFP) and
the Landau mean-field theory or the complete graph (CG) asymptotics. By
large-scale Monte Carlo simulations, we systematically study the interplay of
the GFP and CG effects to the finite-size scaling of percolation above the
upper critical dimension $d_c = 6$ with periodic, free, and cylindrical
boundary conditions. Our results suggest that, with periodic boundaries, the
\emph{unwrapped} correlation length scales as $L^{d/6}$ at the critical point,
diverging faster than $L$ above $d_c$. As a consequence, the scaling behaviours
of macroscopic quantities with respect to the linear system size $L$ follow the
CG asymptotics. The distance-dependent properties, such as the short-distance
behaviour of the two-point correlation function and the Fourier transformed
quantities with non-zero modes, are still controlled by the GFP. With free
boundaries, since the correlation length is cutoff by $L$, the finite-size
scaling at the critical point is controlled by the GFP. However, some
quantities are observed to exhibit the CG aysmptotics at the low-temperature
pseudo-critical point, such as the sizes of the two largest clusters. With
cylindrical boundaries, due to the interplay of the GFP and CG effects, the
correlation length along the axial direction of the cylinder scales as $\xi_L
\sim L^{(d-1)/5}$ within the critical window of size $O(L^{-2(d-1)/5})$,
distinct from both periodic and free boundaries. A field-theoretical
calculation for deriving the scaling of $\xi_L$ is also presented. Moreover,
the one-point surface correlation function along the axial direction of the
cylinder is observed to scale as ${\tau}^{(1-d)/2}$ for short distance but then
enter a plateau of order $L^{-3(d-1)/5}$ before it decays significantly fast.
Thermal-electric conversion is crucial for smart energy control and
harvesting, such as thermal sensing and waste heat recovering. So far, people
are aware of two main ways of direct thermal-electric conversion, Seebeck and
pyroelectric effects, each with different working mechanisms, conditions and
limitations. Here, we report the concept of "Geometric Thermoelectric Pump", as
the third way of thermal-electric conversion beyond Seebeck and pyroelectric
effects. In contrast to Seebeck effect that requires spatial temperature
difference, Geometric Thermoelectric Pump converts the time-dependent ambient
temperature fluctuation into electricity. Moreover, Geometric Thermoelectric
Pump does not require polar materials but applies to general conducting
systems, thus is also distinct from pyroelectric effect. We demonstrate that
Geometric Thermoelectric Pump results from the temperature-fluctuation-induced
charge redistribution, which has a deep connection to the topological geometric
phase in non-Hermitian dynamics, as a consequence of the fundamental
nonequilibrium thermodynamic geometry. The findings advance our understanding
of geometric phase induced multiple-physics-coupled pump effect and provide new
means of thermal-electric energy harvesting.
We use stochastic expansion and exact diagonalization to study the
magic-angle twisted bilayer graphene (TBG) on a disordered substrate. We show
that the substrate-induced strong Coulomb disorder in TBG with the chemical
potential at the level of the flatbands drives the system to a network of
weakly coupled Sachdev-Ye-Kitaev (SYK) bundles, stabilizing an emergent quantum
chaotic strange metal (SM) phase of TBG that exhibits the absence of
quasiparticles. The Gaussian orthogonal ensemble dominates TBG's long-time
chaotic dynamics at strong disorder, whereas fast quantum scrambling appears in
the short-time dynamics. In weak disorder, gapped phases of TBG exhibit
exponentially decaying specific heat capacity and exponential decay in
out-of-time-ordered correlators (OTOC). This is the system behavior in
correlated insulator and superconducting phases, in agreement with the
corresponding Larkin-Ovchinnikov result for correlators. The result suggests a
low-temperature transition from the superconducting and correlated insulating
phases into the strange metal upon increasing the disorder strength. We propose
a finite-temperature phase diagram for Coulomb-disordered TBG and discuss the
experimental consequences of the emergent SM phase.
A variety of analytical approaches have been developed for the study of
quantum spin systems in two dimensions, the notable ones being spin-waves,
slave boson/fermion parton constructions, and for lattices with one-to-one
local correspondence of faces and vertices, the 2D Jordan-Wigner (JW)
fermionization. Field-theoretically, JW fermionization is implemented through
Chern-Simons (CS) flux attachment. For a correct fermionization of lattice
quantum spin-$1/2$ magnets, it is necessary that the fermions obey mutual
bosonic (anyonic) statistics under exchange - this is not possible to implement
on arbitrary 2D lattices if fermionic matter couples only to the lattice gauge
fields. Enlarging the gauge degrees of freedom to include the dual lattice
allows the construction of consistent mutual Chern-Simons field theories. Here
we propose a mutual CS theory where the microscopic (spin) degrees of freedom
are represented as lattice fermionic matter additionally coupled to specific
combinations of dual lattice gauge fields that depend on the local geometry. We
illustrate the use of this method for understanding the properties of a
honeycomb Kitaev model subjected to a strong Zeeman field in the $z$-direction.
Our CS gauge theory framework provides an understanding why the topological
phase is degraded at lower (higher) critical fields for the ferro- (antiferro-)
magnetic Kitaev interaction. Additionally, we observe an effectively
one-dimensional character of the low-excitations at higher fields in the
$z$-direction which we also confirm by spin-wave calculations.
Odd-frequency superconductivity is an exotic superconducting state in which
the symmetry of the gap function is odd in frequency. Here we show that an
inherent odd-frequency mode emerges dynamically under application of a Lorentz
transformation of the anomalous Green function with the general
frequency-dependent gap function. To see this, we consider a Dirac model with
quartic potential and perform a mean-field analysis to obtain a relativistic
Bogoliubov-de Gennes system. Solving the resulting Gor'kov equations yields
expressions for relativistic normal and anomalous Green functions. The form of
the relativistically invariant pairing term is chosen such that it reduces to
BCS form in the non-relativistic limit. We choose an ansatz for the gap
function in a particular frame which is even-frequency and analyze the effects
on the anomalous Green function under a boost into a relativistic frame. The
odd-frequency pairing emerges dynamically as a result of the boost. In the
boosted frame the order parameter contains terms which are both even and odd in
frequency. The relativistic correction to the anomalous Green function to first
order in the boost parameter is completely odd in frequency. This work provides
evidence that odd-frequency pairing may form intrinsically within relativistic
superconductors.
Chalcogenide phase-change materials (PCMs) are widely applied in electronic
and photonic applications, such as non-volatile memory and neuro-inspired
computing. Doped Sb$_2$Te alloys are now gaining increasing attention for
on-chip photonic applications, due to their growth-driven crystallization
features. However, it remains unknown whether Sb$_2$Te also forms a metastable
crystalline phase upon nanoseconds crystallization in devices, similar to the
case of nucleation-driven Ge-Sb-Te alloys. Here, we carry out ab initio
simulations to understand the changes in optical properties of amorphous
Sb$_2$Te upon crystallization and post annealing. During the continuous
transformation process, changes in the dielectric function are highly
wavelength-dependent from the visible-light range towards the telecommunication
band. Our finite-difference time-domain simulations based on the ab initio
input reveal key differences in device output for color display and photonic
memory applications upon tellurium ordering. Our work serves as an example of
how multiscale simulations of materials can guide practical photonic
phase-change applications.
A heat conduction equation on a lattice composed of nodes and bonds is
formulated assuming the Fourier law and the energy conservation law. Based on
this equation, we propose a higher-order topological heat conduction model on
the breathing kagome lattice. We show that the temperature measurement at a
conner node can detect the corner state which causes rapid heat conduction
toward the heat bath, and that several-nodes measurement can determine the
precise energy of the corner states.
We investigate the nature of quantum phases arising in chiral interacting
Hamiltonians recently realized in Rydberg atom arrays. We classify all possible
fermionic chiral spin liquids with $\mathrm{U}(1)$ global symmetry using parton
construction on the honeycomb lattice. The resulting classification includes
six distinct classes of gapped quantum spin liquids: the corresponding
variational wave functions obtained from two of these classes accurately
describe the Rydberg many-body ground state at $1/2$ and $1/4$ particle
density. Complementing this analysis with tensor network simulations, we
conclude that both particle filling sectors host a spin liquid with the same
topological order of a $\nu=1/2$ fractional quantum Hall effect. At density
$1/2$, our results clarify the phase diagram of the model, while at density
$1/4$, they provide an explicit construction of the ground state wave function
with almost unit overlap with the microscopic one. These findings pave the way
to the use of parton wave functions to guide the discovery of quantum spin
liquids in chiral Rydberg models.
As a series of work about 5D (spacetime) topological orders, here we employ
the path-integral formalism of 5D topological quantum field theory (TQFT)
established in Zhang and Ye, JHEP 04 (2022) 138 to explore non-Abelian fusion
rules, hierarchical shrinking rules and quantum dimensions of particle-like,
loop-like and membrane-like topological excitations in 5D topological orders.
To illustrate, we focus on a prototypical example of twisted $BF$ theories that
comprise the twisted topological terms of the $BBA$ type. First, we classify
topological excitations by establishing equivalence classes among all
gauge-invariant Wilson operators. Then, we compute fusion rules from the
path-integral and find that fusion rules may be of non-Abelian nature, i.e.,
the fusion outcome can be a direct sum of distinct excitations. We further
compute shrinking rules. Especially, we discover exotic hierarchical structures
hidden in shrinking processes of 5D or higher: a membrane is shrunk into
particles and loops, and the loops are subsequently shrunk into a direct sum of
particles. We obtain the algebraic structure of shrinking coefficients and
fusion coefficients. We compute the quantum dimensions of all excitations and
find that sphere-like membranes and torus-like membranes differ not only by
their shapes but also by their quantum dimensions. We further study the
algebraic structure that determines anomaly-free conditions on fusion
coefficients and shrinking coefficients. Besides $BBA$, we explore general
properties of all twisted terms in $5$D. Together with braiding statistics
reported before, the theoretical progress here paves the way toward
characterizing and classifying topological orders in higher dimensions where
topological excitations consist of both particles and spatially extended
objects.
Universal topological data of topologically ordered phases can be captured by
topological quantum field theory in continuous space time by taking the limit
of low energies and long wavelengths. While previous continuum
field-theoretical studies of topological orders in $3$D real space focus on
either self-statistics, braiding statistics, shrinking rules, fusion rules or
quantum dimensions, it is yet to systematically put all topological data
together in a unified continuum field-theoretical framework. Here, we construct
the topological $BF$ field theory with twisted terms (e.g., $AAdA$ and $AAB$)
as well as a $K$-matrix $BB$ term, in order to simultaneously explore all such
topological data and reach anomaly-free topological orders. Following the
spirit of the famous $K$-matrix Chern-Simons theory of $2$D topological orders,
we present general formulas and systematically show how the $K$-matrix $BB$
term confines topological excitations, and how self-statistics of particles is
transmuted between bosonic one and fermionic one. In order to reach
anomaly-free topological orders, we explore, within the present continuum
field-theoretical framework, how the principle of gauge invariance
fundamentally influences possible realizations of topological data. More
concretely, we present the topological actions of (i) particle-loop braidings
with emergent fermions, (ii) multiloop braidings with emergent fermions, and
(iii) Borromean-Rings braidings with emergent fermions, and calculate their
universal topological data. Together with the previous efforts, our work paves
the way toward a more systematic and complete continuum field-theoretical
analysis of exotic topological properties of $3$D topological orders. Several
interesting future directions are also discussed.
Magic angle twisted bilayer graphene (MATBG) has become one of the prominent
topics in Condensed Matter during the last few years, however, fully atomistic
studies of the interacting physics are missing. In this work, we study the
correlated insulator states of MATBG in the setting of a tight-binding model,
under a perpendicular magnetic field of $0$ and $26.5$ T, corresponding to zero
and one quantum of magnetic flux per unit cell. At zero field and for dopings
of two holes ($\nu=-2$) or two electrons ($\nu=+2$) per unit cell, the Kramers
intervalley coherent (KIVC) order is the ground state at the Hartree-Fock
level, although it is stabilized by a different mechanism to that in continuum
model. At charge neutrality, the spin polarized state is competitive with the
KIVC due to the on-site Hubbard energy. We obtain a strongly electron-hole
asymmetric phase diagram with robust insulators for electron filling and metals
for negative filling. In the presence of magnetic flux, we predict an insulator
with Chern number $-2$ for $\nu=-2$, a spin polarized state at charge
neutrality and competing insulators with Chern numbers $+2$ and $0$ at
$\nu=+2$. The stability of the $\nu=+2$ insulators is determined by the
screening environment, allowing for the possibility of observing a topological
phase transition.
In our previous work, we synthesized a metal/2D material heterointerface
consisting of $L1_0$-ordered iron-palladium (FePd) and graphene (Gr) called
FePd(001)/Gr. This system has been explored by both experimental measurements
and theoretical calculations. In this study, we focus on a heterojunction
composed of FePd and multilayer graphene referred to as
FePd(001)/$m$-Gr/FePd(001), where $m$ represents the number of graphene layers.
We perform first-principles calculations to predict their spin-dependent
transport properties. The quantitative calculations of spin-resolved
conductance and magnetoresistance (MR) ratio (150-200%) suggest that the
proposed structure can function as a magnetic tunnel junction in spintronics
applications. We also find that an increase in $m$ not only reduces conductance
but also changes transport properties from the tunneling behavior to the
graphite $\pi$-band-like behavior. Furthermore, we examine the impact of
lateral displacements (sliding) at the interface and find that the spin
transport properties remain robust despite these changes; this is the advantage
of two-dimensional material hetero-interfaces over traditional insulating
barrier layers such as MgO.

Date of feed: Wed, 09 Aug 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]+) **Business models to assure availability of advanced superconductors for the accelerator sector and promote stewardship of superconducting magnet technology for the US economy. (arXiv:2308.03808v1 [physics.acc-ph])**

Lance Cooley, Kathleen Amm, Whitney Hischier, Steven Rotkoff, David Larbalestier

**Honeycomb Layered Frameworks with Metallophilic Bilayers. (arXiv:2308.03809v1 [cond-mat.mtrl-sci])**

Godwill Mbiti Kanyolo, Titus Masese, Yoshinobu Miyazaki, Shintaro Tachibana, Chengchao Zhong, Yuki Orikasa, Tomohiro Saito

**Edge states of 2D time-reversal-invariant topological superconductors with strong interactions and disorder: A view from the lattice. (arXiv:2308.03836v1 [cond-mat.str-el])**

Jun Ho Son, Jason Alicea, Olexei I. Motrunich

**Strongly Interacting Phases in Twisted Bilayer Graphene at the Magic Angle. (arXiv:2308.03843v1 [cond-mat.str-el])**

Khagendra Adhikari, Kangjun Seo, K. S. D. Beach, Bruno Uchoa

**Review on Infrared Nanospectroscopy of Natural 2D Phyllosilicates. (arXiv:2308.03860v1 [cond-mat.mes-hall])**

Raphaela De Oliveira, Alisson R. Cadore, Raul O. Freitas, Ingrid D. Barcelos

**Chirality manipulation of ultrafast phase switchings in a correlated CDW-Weyl semimetal. (arXiv:2308.03895v1 [cond-mat.str-el])**

Bing Cheng, Di Cheng, Tao Jiang, Wei Xia, Boqun Song, Martin Mootz, Liang Luo, Ilias E. Perakis, Yongxin Yao, Yanfeng Guo, Jigang Wang

**Charge Polarization around Impurities in Strained Graphene. (arXiv:2308.03899v1 [cond-mat.mes-hall])**

Mohamed M. Elsayed, Sang Wook Kim, Juan M. Vanegas, Valeri N. Kotov

**Role of pressure in generation of intense velocity gradients in turbulent flows. (arXiv:2308.03902v1 [physics.flu-dyn])**

Dhawal Buaria, Alain Pumir

**Mu-Metal Enhancement of Effects in Electromagnetic Fields Over Single Emitters Near Topological Insulators. (arXiv:2308.03932v1 [cond-mat.mes-hall])**

Eitan Dvorquez, Benjamín Pavez, Qiang Sun, Felipe Pinto, Andrew D. Greentree, Brant C. Gibson, Jerónimo R. Maze

**High Temperature Superconductivity with Strong Correlations and Disorder: Possible Relevance to Cu-doped Apatite. (arXiv:2308.03948v1 [cond-mat.supr-con])**

Maciej Fidrysiak, Andrzej P. Kądzielawa, Józef Spałek

**Perpendicular electronic transport and moir\'{e}-induced resonance in twisted interfaces of 3D graphite. (arXiv:2308.03993v1 [cond-mat.mes-hall])**

Tenta Tani, Takuto Kawakami, Mikito Koshino

**Delocalized polaron and Burstein-Moss shift induced by Li in $\alpha$-$\textrm{V}_{2}\textrm{O}_{5}$: DFT+DMFT study. (arXiv:2308.04043v1 [cond-mat.str-el])**

Huu T. Do, Alex Taekyung Lee, Hyowon Park, Anh Ngo

**Gold Nanoparticles Aggregation on Graphene Using Reactive Force Field: A Molecular Dynamic Study. (arXiv:2308.04089v1 [physics.app-ph])**

J. Hingies Monisha, V. Vasumathi, Prabal K Maiti

**Designing optoelectronic properties by on-surface synthesis: formation and electronic structure of an iron-terpyridine macromolecular complex. (arXiv:2308.04105v1 [cond-mat.mtrl-sci])**

Agustin Schiffrin, Martina Capsoni, Gelareh Farahi, Chen-Guang Wang, Cornelius Krull, Marina Castelli, Tanya S. Roussy, Katherine A. Cochrane, Yuefeng Yin, Nikhil Medhekar, Adam Q. Shaw, Wei Ji, Sarah A. Burke

**Optical Manipulation of the Charge Density Wave state in RbV3Sb5. (arXiv:2308.04128v1 [cond-mat.str-el])**

Yuqing Xing, Seokjin Bae, Ethan Ritz, Fan Yang, Turan Birol, Andrea N. Capa Salinas, Brenden R. Ortiz, Stephen D. Wilson, Ziqiang Wang, Rafael M. Fernandes, Vidya Madhavan

**Electronic and magnetic properties of single chalcogen vacancies in MoS$_2$/Au(111). (arXiv:2308.04139v1 [cond-mat.mes-hall])**

Sergey Trishin, Christian Lotze, Nils Krane, Katharina J. Franke

**Interplay of the complete-graph and Gaussian fixed-point asymptotics in finite-size scaling of percolation above the upper critical dimension. (arXiv:2308.04238v1 [cond-mat.stat-mech])**

Mingzhong Lu, Sheng Fang, Zongzheng Zhou, Youjin Deng

**Geometric Thermoelectric Pump: Energy Harvesting beyond Seebeck and Pyroelectric Effects. (arXiv:1402.3645v2 [cond-mat.mes-hall] UPDATED)**

Jie Ren

**Strange metal phase of disordered magic-angle twisted bilayer graphene at low temperatures: from flatbands to weakly coupled Sachdev-Ye-Kitaev bundles. (arXiv:2205.09766v3 [cond-mat.dis-nn] UPDATED)**

Chenan Wei, Tigran A. Sedrakyan

**Jordan-Wigner fermionization of quantum spin systems on arbitrary 2D lattices: A mutual Chern-Simons approach. (arXiv:2210.07718v2 [cond-mat.str-el] UPDATED)**

Jagannath Das, Aman Kumar, Avijit Maity, Vikram Tripathi

**Appearance of Odd-Frequency Superconductivity in a Relativistic Scenario. (arXiv:2212.01849v3 [cond-mat.supr-con] UPDATED)**

Patrick J. Wong, Alexander V. Balatsky

**Multiscale simulations of growth-dominated Sb$_2$Te phase-change material for non-volatile photonic applications. (arXiv:2301.03146v2 [cond-mat.mtrl-sci] UPDATED)**

Xu-Dong Wang, Wen Zhou, Hangming Zhang, Shehzad Ahmed, Tiankuo Huang, Riccardo Mazzarello, En Ma, Wei Zhang

**Higher-order topological heat conduction on a lattice for detection of corner states. (arXiv:2303.08402v2 [cond-mat.mes-hall] UPDATED)**

T. Fukui, T. Yoshida, Y. Hatsugai

**Classification and emergence of quantum spin liquids in chiral Rydberg models. (arXiv:2303.12829v2 [cond-mat.str-el] UPDATED)**

Poetri Sonya Tarabunga, Giuliano Giudici, Titas Chanda, Marcello Dalmonte

**Fusion rules and shrinking rules of topological orders in five dimensions. (arXiv:2306.14611v2 [hep-th] UPDATED)**

Yizhou Huang, Zhi-Feng Zhang, Peng Ye

**Continuum field theory of 3D topological orders with emergent fermions and braiding statistics. (arXiv:2307.09983v2 [cond-mat.str-el] UPDATED)**

Zhi-Feng Zhang, Qing-Rui Wang, Peng Ye

**The correlated insulators of magic angle twisted bilayer graphene at zero and one quantum of magnetic flux: a tight-binding study. (arXiv:2308.01997v2 [cond-mat.mes-hall] UPDATED)**

Miguel Sánchez Sánchez, Tobias Stauber

**First-principle study of spin transport property in $L1_0$-FePd(001)/graphene heterojunction. (arXiv:2308.02171v2 [cond-mat.mtrl-sci] UPDATED)**

Hayato Adachi, Ryuusuke Endo, Hikari Shinya, Hiroshi Naganuma, Mitsuharu Uemoto

Found 4 papers in prb Layered ternary actinide chalcogenides contain unique structural and magnetic properties that remain underexplored. ${\mathrm{KU}}_{2}{\mathrm{Te}}_{6}$ is a new member of the $A\text{−}R\text{−}Q$ ($A=$ alkali; $R=$ actinide; $Q=$ chalcogenide) materials family crystallizing in the $Cmcm$ space gro… We study the slopes of the upper critical field $S=∂{H}_{{}_{c2}}/∂T$ at the superconducting transition temperature ${T}_{c}$ in anisotropic superconductors with transport (nonmagnetic) scattering employing the Ginzburg-Landau theory, developed for this case by Pokrovsky and Pokrovsky [Phys. Rev. B We present a first-principles computational study of the ${\mathrm{NbS}}_{2}/{\mathrm{WSe}}_{2}$ junction between two transition metal dichalcogenide monolayers as a prototypical metal/semiconductor two-dimensional (2D) lateral heterostructure (LH) to investigate the effects of electrostatic perturb… The potential energy surface (PES) of the interlayer interaction of infinite twisted bilayer graphene is calculated for a set of commensurate moiré patterns using the registry-dependent Kolmogorov-Crespi empirical potential. The calculated PESs have the same shape for all considered moiré patterns, …

Date of feed: Wed, 09 Aug 2023 03:17:06 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+) **Structural anomaly and crystalline electric field excitations in low-dimensional ${\mathrm{KU}}_{2}{\mathrm{Te}}_{6}$**

Mitchell M. Bordelon, Shannon S. Fender, S. M. Thomas, Joe D. Thompson, Eric D. Bauer, and Priscila F. S. Rosa

Author(s): Mitchell M. Bordelon, Shannon S. Fender, S. M. Thomas, Joe D. Thompson, Eric D. Bauer, and Priscila F. S. Rosa

[Phys. Rev. B 108, 064406] Published Tue Aug 08, 2023

**Disorder-dependent slopes of the upper critical field in nodal and nodeless superconductors**

V. G. Kogan and R. Prozorov

Author(s): V. G. Kogan and R. Prozorov**…**

[Phys. Rev. B 108, 064502] Published Tue Aug 08, 2023

**Electrostatic tuning of transmission in ${\mathrm{NbS}}_{2}/{\mathrm{WSe}}_{2}$ two-dimensional lateral heterostructures: A computational study**

Poonam Kumari, Zahra Golsanamlou, Alexander Smogunov, Luca Sementa, and Alessandro Fortunelli

Author(s): Poonam Kumari, Zahra Golsanamlou, Alexander Smogunov, Luca Sementa, and Alessandro Fortunelli

[Phys. Rev. B 108, 075404] Published Tue Aug 08, 2023

**Interlayer interaction, shear vibrational mode, and tribological properties of two-dimensional bilayers with a commensurate moiré pattern**

Alexander S. Minkin, Irina V. Lebedeva, Andrey M. Popov, Sergey A. Vyrko, Nikolai A. Poklonski, and Yurii E. Lozovik

Author(s): Alexander S. Minkin, Irina V. Lebedeva, Andrey M. Popov, Sergey A. Vyrko, Nikolai A. Poklonski, and Yurii E. Lozovik

[Phys. Rev. B 108, 085411] Published Tue Aug 08, 2023

Found 2 papers in prl Thermalization (generalized thermalization) in nonintegrable (integrable) quantum systems requires two ingredients: equilibration and agreement with the predictions of the Gibbs (generalized Gibbs) ensemble. We prove that observables that exhibit eigenstate thermalization in single-particle sector e… Quantum metrology protocols using entangled states of large spin ensembles attempt to achieve measurement sensitivities surpassing the standard quantum limit (SQL), but in many cases they are severely limited by even small amounts of technical noise associated with imperfect sensor readout. Amplific…

Date of feed: Wed, 09 Aug 2023 03:17:07 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]+) **Generalized Thermalization in Quantum-Chaotic Quadratic Hamiltonians**

Patrycja Łydżba, Marcin Mierzejewski, Marcos Rigol, and Lev Vidmar

Author(s): Patrycja Łydżba, Marcin Mierzejewski, Marcos Rigol, and Lev Vidmar

[Phys. Rev. Lett. 131, 060401] Published Tue Aug 08, 2023

**Squeezed Superradiance Enables Robust Entanglement-Enhanced Metrology Even with Highly Imperfect Readout**

Martin Koppenhöfer, Peter Groszkowski, and A. A. Clerk

Author(s): Martin Koppenhöfer, Peter Groszkowski, and A. A. Clerk

[Phys. Rev. Lett. 131, 060802] Published Tue Aug 08, 2023

Found 2 papers in pr_res We use the configuration model to generate random networks having a degree distribution that follows a $q$-exponential, ${P}_{q}(k)=(2−q)λ{[1−(1−q)λk]}^{−1/(q−1)}$, for arbitrary values of the parameters $q$ and $λ$. Typically, for small values of $λ$, this distribution crosses over from a plateau a… Global quenches of quantum many-body models can give rise to periodic dynamical quantum phase transitions (DQPTs) directly connected to the zeros of a Landau order parameter (OP). The associated dynamics has been argued to bear a close resemblance to Rabi oscillations characteristic of two-level sys…

Date of feed: Wed, 09 Aug 2023 03:17:06 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+) **Random networks with $q$-exponential degree distribution**

Cesar I. N. Sampaio Filho, Marcio M. Bastos, Hans J. Herrmann, André A. Moreira, and José S. Andrade, Jr.

Author(s): Cesar I. N. Sampaio Filho, Marcio M. Bastos, Hans J. Herrmann, André A. Moreira, and José S. Andrade, Jr.

[Phys. Rev. Research 5, 033088] Published Tue Aug 08, 2023

**Anatomy of dynamical quantum phase transitions**

Maarten Van Damme, Jean-Yves Desaules, Zlatko Papić, and Jad C. Halimeh

Author(s): Maarten Van Damme, Jean-Yves Desaules, Zlatko Papić, and Jad C. Halimeh

[Phys. Rev. Research 5, 033090] Published Tue Aug 08, 2023