Found 36 papers in cond-mat Charge injection mechanism from contact electrodes into two-dimensional (2D)
dichalcogenides is an essential topic for exploiting electronics based on 2D
channels, but remains not well understood. Here, low-work-function metal
ytterbium (Yb) was employed as contacts for tungsten disulfide (WS$_2$) to
understand the realistic injection mechanism. The contact properties in WS$_2$
with variable temperature (T) and channel thickness (tch) were synergetically
characterized. It is found that the Yb/WS$_2$ interfaces exhibit a strong
pinning effect between energy levels and a low contact resistance ($R_\rm{C}$)
value down to $5\,k\Omega\cdot\mu$m. Cryogenic electrical measurements reveal
that $R_\rm{C}$ exhibits weakly positive dependence on T till 77 K, as well as
a weakly negative correlation with tch. In contrast to the non-negligible
$R_\rm{C}$ values extracted, an unexpectedly low effective thermal injection
barrier of 36 meV is estimated, indicating the presence of significant
tunneling injection in subthreshold regime and the inapplicability of the pure
thermionic emission model to estimate the height of injection barrier.
We propose a semi-suspended device structure and construct nanogapped,
hysteresis-free field-effect transistors (FETs), based on the van der Waals
stacking technique. The structure, which features a semi-suspended channel
above a submicron-long wedge-like nanogap, is fulfilled by transferring
ultraclean BN-supported MoS$_2$ channels directly onto dielectric-spaced
vertical source/drain stacks. Electronic characterization and analyses reveal a
high overall device quality, including ultraclean channel interfaces,
negligible electrical scanning hysteresis, and Ohmic contacts in the
structures. The unique hollow FET structure holds the potential for exploiting
reliable electronics, as well as nanofluid and pressure sensors.
Device passivation through ultraclean hexagonal BN encapsulation is proven
one of the most effective ways for constructing high-quality devices with
atomically thin semiconductors that preserves the ultraclean interface quality
and intrinsic charge transport behavior. However, it remains challenging to
integrate lithography compatible contact electrodes with flexible distributions
and patterns. Here, we report the feasibility in straightforwardly integrating
lithography defined contacts into BN encapsulated 2D FETs, giving rise to
overall device quality comparable to the state-of-the-art results from the
painstaking pure dry transfer processing. Electronic characterization on FETs
consisting of WSe$_2$ and MoS$_2$ channels reveals an extremely low scanning
hysteresis of ca. 2 mV on average, a low density of interfacial charged
impurity of ca. $10^{11}\,$cm$^{-2}$, and generally high charge mobilities over
$1000\,$cm$^{2}\cdot$V$^{-1}\cdot$s$^{-1}$ at low temperatures. The overall
high device qualities verify the viability in directly integrating lithography
defined contacts into BN encapsulated devices to exploit their intrinsic charge
transport properties for advanced electronics.
Topological insulators and giant spin-orbit toque switching of nanomagnets
are one of the frontier topics for the development of energy-efficient
spintronic devices. Spin-circuit representations involving different materials
and phenomena are quite well-established now for its prowess of interpreting
experimental results and then designing complex and efficient functional
devices. Here, we construct the spin-circuit representation of spin pumping
into topological insulators considering both the bulk and surface states with
parallel channels, which allows the interpretation of practical experimental
results. We show that the high increase in effective spin mixing conductance
and inverse spin Hall voltages cannot be explained by the low-conductive bulk
states of topological insulators. We determine high spin Hall angle close to
the maximum magnitude of one from experimental results and with an eye to
design efficient spin devices, we further employ a spin-sink layer in the
spin-circuit formalism to increase the effective spin mixing conductance at low
thicknesses and double the inverse spin Hall voltage.
The studies of a number of systems treated in terms of an inhomogeneous
(spatially separated) Fermi-Bose mixture with superconducting clusters or
droplets of the order parameter in a host medium with unpaired normal states
are reviewed. A spatially separated Fermi-Bose mixture is relevant to
superconducting BaKBiO3 bismuth oxides. Droplets of the order parameter can
occur in thin films of a dirty metal, described in the framework of the
strongly attractive two-dimensional Hubbard model at a low electron density
with a clearly pronounced diagonal disorder. The Bose-Einstein condensate
droplets are formed in mixtures and dipole gases with an imbalance in the
densities of the Fermi and Bose components. The Bose-Einstein condensate
clusters also arise at the center or at the periphery of a magnetic trap
involving spin-polarized Fermi gases. Exciton and plasmon collapsing droplets
can emerge in the presence of the exciton-exciton or plasmon-plasmon
interaction. The plasmon contribution to the charge screening in MgB2 leads to
the formation of spatially modulated inhomogeneous structures. In metallic
hydrogen and metal hydrides, droplets can be formed in shock-wave experiments
at the boundary of the first-order phase transition between the metallic and
molecular phases. In a spatially separated Fermi-Bose mixture arising in an
Aharonov-Bohm interference ring with a superconducting bridge in a
topologically nontrivial state, additional Fano resonances may appear and
collapse due to the presence of edge Majorana modes in the system.
The optical and electronic properties of multilayer transition metal
dichalcogenides differ significantly from their monolayer counterparts due to
interlayer interactions. The separation of individual layers can be tuned in a
controlled way by applying pressure. Here, we use a diamond anvil cell to
compress bilayers of 2H-MoS$_2$ in the gigapascal range. By measuring optical
transmission spectra, we find that increasing pressure leads to a decrease in
the energy splitting between the A and interlayer exciton. Comparing our
experimental findings with ab initio calculations, we conclude that the
observed changes are not due to the commonly assumed hydrostatic compression.
This effect is attributed to the MoS$_2$ bilayer adhering to the diamond, which
reduces in-plane compression. Moreover, we demonstrate that the distinct
real-space distributions and resulting contributions from the valence band
account for the different pressure dependencies of the inter- and intralayer
excitons in compressed MoS$_2$ bilayers.
The formation of topological defects after a symmetry-breaking phase
transition is an overarching phenomenon that encodes rich information about the
underlying dynamics. Kibble-Zurek mechanism (KZM), which describes these
nonequilibrium dynamics, predicts defect densities of these second-order phase
transitions driven by thermal fluctuations. It has been verified as a
successful model in a wide variety of physical systems, finding applications
from structure formation in the early universe to condensed matter systems.
However, whether topologically-trivial Ising domains, one of the most common
and fundamental types of domains in condensed matter systems, also obey the KZM
has never been investigated in the laboratory. We examined two different kinds
of three-dimensional (3D) structural Ising domains: clockwise
(CW)/counter-clockwise (CCW) ferro-rotation domains in NiTiO3 and up/down polar
domains in BiTeI. While the KZM slope of ferro-rotation domains in NiTiO3
agrees well with the prediction of the 3D Ising model, the KZM slope of polar
domains in BiTeI surprisingly far exceeds the theoretical limit, setting an
exotic example where possible weak long-range dipolar interactions play a
critical role in steepening the KZM slope of non-topological quantities. Our
results demonstrate the validity of KZM for Ising domains and reveal an
enhancement of the power-law exponent and a possible reduction of the dynamic
critical exponent z for transitions with long-range interactions.
Sterically encumbering m-terphenyl isocyanides are a class of metal-binding
group that foster low-coordinate metal-center environments in coordination
chemistry by exerting considerable intermolecular steric pressures between
neighboring ligands. In the context of metal surfaces, the encumbering steric
properties of the m-terphenyl isocyanides are shown to weaken the interaction
between the metal-binding group and a planar substrate, leading to a preference
for molecular adsorption at sites with convex curvature, such as the step edges
and herringbone elbow sites on Au(111). Here, we investigate the site-selective
binding of individual m-terphenyl isocyanide ligands on a Au(111) surface
through scanning tunneling microscopy (STM) and inelastic electron tunneling
spectroscopy (IETS). The site-dependent steric pressure alters the vibrational
fingerprint of the m-terphenyl isocyanides, which is characterized with
single-molecule precision through joint experimental and theoretical
approaches. This study for the first time provides molecular-level insights
into the steric-pressure-enabled surface binding selectivity as well as its
effect on the chemical properties of individual m-terphenyl isocyanide ligands,
thereby highlighting the potential to control the physical and chemical
properties of metal surfaces through tailored ligand design.
We studied the interlayer coupling and decoupling of bilayer graphene (BLG)
by using spatially resolved electron energy loss spectroscopy (EELS) with a
monochromated electron source. We correlated the twist-angle-dependent energy
band hybridization with Moire superlattices and the corresponding optical
absorption peaks. The optical absorption peak originates from the excitonic
transition between the hybridized van Hove singularities (vHSs), which shifts
systematically with the twist angle. We then proved that the BLG decouples when
a monolayer of metal chloride is intercalated in its van der Waals (vdW) gap,
and results in the elimination of the vHS peak.
Magnetic multiple-$Q$ states consisting of multiple spin density waves are a
source of unconventional topological spin textures, such as skyrmion and
hedgehog. We theoretically investigate a topologically nontrivial double-$Q$
state with a net spin scalar chirality on a two-dimensional square lattice. We
find that a double-$Q$ spiral superposition of the ordering wave vectors
located at the Brillouin zone boundary gives rise to unconventional noncoplanar
spin textures distinct from the skyrmion crystal. We show that such a
double-$Q$ state is stabilized by the interplay among the easy-axis anisotropic
interaction, high-harmonic wave-vector interaction, and external magnetic
field. Furthermore, the obtained double-$Q$ state becomes a Chern insulating
state with a quantum Hall conductivity when the Fermi level is located in the
band gaps. Our present results provide another platform to realize topological
magnetic states other than skyrmion crystals by focusing on the symmetry of
constituent ordering wave vectors in momentum space.
We propose an experimentally feasible dissipative spin-wave diode comprising
two magnetic layers coupled via a non-magnetic spacer. We theoretically
demonstrate that the spacer mediates not only coherent interactions but also
dissipative coupling. Interestingly, an appropriately engineered dissipation
engenders a nonreciprocal device response, facilitating the realization of a
spin-wave diode. This diode permits wave propagation in one direction alone,
given that the coherent Dzyaloshinskii- Moriya (DM) interaction is balanced
with the dissipative coupling. The polarity of the diode is determined by the
sign of the DM interaction. Furthermore, we show that when the magnetic layers
undergo incoherent pumping, the device operates as a unidirectional spin-wave
amplifier. The amplifier gain is augmented by cascading multiple magnetic
bilayers. By extending our model to a one-dimensional ring structure, we
establish a connection between the physics of spin-wave amplification and
non-Hermitian topology. Our proposal opens up a new avenue for harnessing
inherent dissipation in spintronic applications.
The fusion basis of Fibonacci anyons supports unitary braid representations
that can be utilized for universal quantum computation. We show a mapping
between the fusion basis of three Fibonacci anyons, $\{|1\rangle,
|\tau\rangle\}$, and the two length 4 Dyck paths via an isomorphism between the
two dimensional braid group representations on the fusion basis and the braid
group representation built on the standard $(2,2)$ Young diagrams using the
Jones construction. This correspondence helps us construct the fusion basis of
the Fibonacci anyons using Dyck paths as the number of standard $(N,N)$ Young
tableaux is the Catalan number, $C_N$ . We then use the local Fredkin moves to
construct a spin chain that contains precisely those Dyck paths that correspond
to the Fibonacci fusion basis, as a degenerate set. We show that the system is
gapped and examine its stability to random noise thereby establishing its
usefulness as a platform for topological quantum computation. Finally, we show
braidwords in this rotated space that efficiently enable the execution of any
desired single-qubit operation, achieving the desired level of precision($\sim
10^{-3}$).
Atomically precise graphene nanoribbons (GNRs) are predicted to exhibit
exceptional edge-related properties, such as localized edge states, spin
polarization, and half-metallicity. However, the absence of low-resistance
nano-scale electrical contacts to the GNRs hinders harnessing their properties
in field-effect transistors. In this paper, we make electrical contact with
9-atom-wide armchair GNRs using superconducting alloy MoRe as well as Pd (as a
reference), which are two of the metals providing low-resistance contacts to
carbon nanotubes. We take a step towards contacting a single GNR by fabrication
of electrodes with a needle-like geometry, with about 20 nm tip diameter and 10
nm separation. To preserve the nano-scale geometry of the contacts, we develop
a PMMA-assisted technique to transfer the GNRs onto the pre-patterned
electrodes. Our device characterizations as a function of bias-voltage and
temperature, show a thermally-activated gate-tunable conductance in the
GNR-MoRe-based transistors.
Single cobalt atoms on the (111) surfaces of noble metals were for a long
time considered prototypical systems for the Kondo effect in scanning tunneling
microscopy experiments. Yet, recent first-principle calculations suggest that
the experimentally observed spectroscopic zero-bias anomaly (ZBA) should be
interpreted in terms of excitations of the Co atom's spin and the formation of
a novel quasiparticle, the spinaron, a magnetic polaron resulting from the
interaction of spin excitations with conduction electrons, rather than in terms
of a Kondo resonance. Here we present state-of-the-art spin-averaged and
spin-polarized scanning tunneling spectroscopy measurements on Co atoms on the
Cu(111) surface in magnetic fields of up to 12 T, that allow us to discriminate
between the different theoretical models and to invalidate the prevailing
Kondo-based interpretation of the ZBA. Employing extended ab-initio
calculations, we instead provide strong evidence for multiple spinaronic states
in the system. Our work opens a new avenue of research to explore the
characteristics and consequences of these intriguing hybrid many-body states as
well as their design in man-made nanostructures.
Monolayer (1L) transition metal dichalcogenides (TMDC) are of strong interest
in nanophotonics due to their narrow-band intense excitonic transitions
persisting up to room temperature. When brought into resonance with surface
plasmon polariton (SPP) excitations of a conductive medium opportunities for
studying and engineering strong light-matter coupling arise. Here, we consider
a most simple geometry, namely a planar stack composed of a thin silver film,
an Al2O3 spacer and a monolayer of WS2. We perform total internal reflection
ellipsometry which combines spectroscopic ellipsometry with the
Kretschmann-Raether-type surface plasmon resonance configuration. The combined
amplitude and phase response of the reflected light at varied angle of
incidence proves that despite the atomic thinness of 1L-WS2, the strong
coupling (SC) regime between A excitons and SPPs propagating in the thin Ag
film is reached. The phasor representation of rho corroborates SC as rho
undergoes a topology change indicated by the occurrence of a double point at
the cross over from the weak to the strong coupling regime. Our findings are
validated by both analytical transfer matrix method calculations and numerical
Maxwell simulations. The findings open up new perspectives for applications in
plasmonic modulators and sensors benefitting from the tunability of the optical
properties of 1L-TMDCs by electric fields, electrostatic doping, light and the
chemical environment.
Influence of the transverse uniform magnetic field $\bf B$ on position
(subscript $\rho$) and momentum ($\gamma$) Shannon quantum-information
entropies $S_{\rho,\gamma}$, Fisher informations $I_{\rho,\gamma}$ and
informational energies $O_{\rho,\gamma}$ is studied theoretically for the 2D
circular quantum dots (QDs) whose circumference supports homogeneous either
Dirichlet or Neumann boundary condition (BC). Analysis reveals similarities and
differences of the influence on the properties of the structure of the surface
interaction with the magnetic field. Conspicuous distinction between the
spectra are crossings at the increasing induction of the Neumann energies with
the same radial quantum number $n$ and adjacent non-positive angular indices
$m$. At the growing $B$, either system undergoes Landau condensation when its
characteristics turn into their uniform field counterparts. For the Dirichlet
system this transformation takes place at the smaller magnetic intensities;
e.g., the Dirichlet sum $S_{\rho_{00}}+S_{\gamma_{00}}$ on its approach from
above to a fundamental limit $2(1+\ln\pi)$ is at any $B$ smaller than the
corresponding Neumann quantity what physically means that the former geometry
provides more total information about the position and motion of the particle.
It is pointed out that the widely accepted disequilibrium uncertainty relation
$O_\rho O_\gamma\leq(2\pi)^{-\mathtt{d}}$, with $\mathtt{d}$ being a
dimensionality of the system, is violated by the Neumann QD in the magnetic
field. Comparison with electrostatic harmonic confinement is performed.
Physical interpretation is based on the different roles of the two BCs and
their interplay with the field: Dirichlet (Neumann) surface is a repulsive
(attractive) interface.
In this work, a generalized force-field methodology for the relaxation of
large moir\'e heterostructures is proposed. The force-field parameters are
optimized to accurately reproduce the structural degrees of freedom of some
computationally manageable cells relaxed using density functional theory. The
parameters can then be used to handle large moir\'e systems. We specialize to
the case of 2H-phased twisted transition-metal dichalcogenide homo- and
heterobilayers using a combination of the Stillinger-Weber intralayer- and the
Kolmogorov-Crespi interlayer-potential. Force-field parameters are developed
for all combinations of MX$_2$ for $\text{M}\in\{\text{Mo},\text{W}\}$ and
$\text{X}\in\{\text{S},\text{Se},\text{Te}\}$. The results show agreement
within 20 meV in terms of band structure between density functional theory and
force-field relaxation. Using the relaxed structures, a simplified and
systematic scheme for the extraction of the interlayer moir\'e potential is
presented for both R- and H-stacked systems. We show that in-plane and
out-of-plane relaxation effects on the moir\'e potential, which is made both
deeper and wider after relaxation, are essential. An interpolation based
methodology for the calculation of the interlayer binding energy is also
proposed. Finally, we show that atomic reconstruction, which is captured by the
force-field method, becomes especially prominent for angles below 4-5$^\circ$,
when there is no mismatch in lattice constant between layers.
Motivated by the search for chiral spin liquids (CSL), we consider a simple
model defined on the kagome lattice of interacting SU(3) spins (in the
fundamental representation) including two-site and three-site permutations
between nearest neighbor sites and on triangles, respectively. By combining
analytical developments and various numerical techniques, namely exact Lanczos
diagonalizations and tensor network variational approaches, we find a rich
phase diagram with non-topological (``trivial") and topological (possibly
chiral) gapped spin liquids (SLs). Trivial spin liquids include an
Affleck-Kennedy-Lieb-Tasaki (AKLT)-like phase and a trimerized phase, the
latter breaking the inversion center between the up and down triangles of the
kagome lattice. A topological SL is stabilized in a restricted part of the
phase diagram by the time-reversal symmetry breaking (complex) 3-site
permutation term. Analyzing the chiral edge modes of this topological SL on
long cylinders or on finite disks, we have come up with two competing
scenarios, either a CSL or a double Chern-Simon SL characterized by a single or
by two counter-propagating Wess-Zumino-Witten SU(3)$_1$ chiral mode(s),
respectively. In the vicinity of the extended ferromagnetic region we have
found a magnetic phase corresponding either to a modulated canted ferromagnet
or to a uniform partially magnetized ferromagnet.
Hybrid Josephson junctions realized on a two-dimensional electron gas are
considered promising candidates for developing topological elements that are
easily controllable and scalable. Here, we theoretically study the possibility
of the detection of topological superconductivity via the non-local
spectroscopy technique. We show that the non-local conductance is related to
the system band structure, allowing probe of the gap closing and reopening
related to the topological transition. We demonstrate that the topological
transition induces a change in the sign of the non-local conductance at zero
energy due to the change in the quasiparticle character of the dispersion at
zero momentum. Importantly, we find that the tunability of the superconducting
phase difference via flux in hybrid Josephson junctions systems is strongly
influenced by the strength of the Zeeman interaction, which leads to
considerable modifications in the complete phase diagram that can be measured
under realistic experimental conditions.
We compute the momentum resolved dynamical spin structure factor
$S(k,\omega)$ of the SU(4) Heisenberg model on the honeycomb lattice assuming
the $\pi$-flux Dirac spin liquid ground state by two methods: (i) variationally
using Gutzwiller projected particle-hole excitations of the $\pi$-flux Fermi
sea and (ii) in the non-interacting parton mean-field picture. The two
approaches produce qualitatively similar results. Based on this analogy, we
argue that the energy spectrum of the projected excitations is a gapless
continuum of fractional excitations. Quantitatively, the Gutzwiller projection
shifts the weight from higher to lower energies, thus emphasizing the lower
edge of the continuum. In the mean-field approach, we obtained the
$1/\text{distance}^4$ decay of the spin correlation function, and the local
correlations show $S^{33}_{\text{MF}}(\omega)\propto \omega^3$ behavior.
The possibility to engineer artificial Kitaev chains in arrays of quantum
dots coupled via narrow superconducting regions has emerged as an attractive
way to overcome the disorder issues that complicate the realization and
detection of topological superconducting phases in other platforms. Although a
true topological phase would require long chains, already a two-site chain
realized in a double quantum dot can be tuned to points in parameter space
where it hosts zero-energy states that seem identical to the Majorana bound
states that characterize a topological phase. These states were named "poor
man's Majorana bound states" (PMMs) because they lack formal topological
protection. In this work, we propose a roadmap for next-generation experiments
on PMMs. The roadmap starts with experiments to characterize a single pair of
PMMs by measuring the Majorana quality, then moves on to initialization and
readout of the parity of a PMM pair, which allows measuring quasiparticle
poisoning times. The next step is to couple two PMM systems to form a qubit. We
discuss measurements of the coherence time of such a qubit, as well as a test
of Majorana fusion rules in the same setup. Finally, we propose and analyse
three different types of braiding-like experiments which require more complex
device geometries. Our conclusions are supported by calculations based on a
realistic model with interacting and spinful quantum dots, as well as by
simpler models to gain physical insight. Our calculations show that it is
indeed possible to demonstrate nonabelian physics in minimal two-site Kitaev
chains despite the lack of a true topological phase. But our findings also
reveal that doing so requires some extra care, appropriately modified protocols
and awareness of the details of this particular platform.
The recently discovered layered kagome superconductors
$\textit{A}$V$_{3}$Sb$_{5}$ ($\textit{A}$ = K, Rb, Cs) have garnered
significant attention, as they exhibit an intriguing combination of
superconductivity, charge density wave (CDW) order, and nontrivial band
topology. As such, these kagome systems serve as an exceptional quantum
platform for investigating the intricate interplay between electron correlation
effects, geometric frustration, and topological electronic structure. A
comprehensive understanding of the underlying electronic structure is crucial
for unveiling the nature and origin of the CDW order, as well as determining
the electron pairing symmetry in the kagome superconductors. In this review, we
present a concise survey of the electronic properties of
$\textit{A}$V$_{3}$Sb$_{5}$, with a particular focus on the insights derived
from angle-resolved photoemission spectroscopy (ARPES). Through the lens of
ARPES, we shed light on the electronic characteristics of the kagome
superconductors $\textit{A}$V$_{3}$Sb$_{5}$, which will pave the way for
exciting new research frontiers in kagome-related physics.
Within a Supersymmetric Quantum Mechanics (SUSY-QM) framework, the (3+1)
Dirac equation describing a Dirac material in the presence of external parallel
electric and magnetic fields is solved. Considering static but non-uniform
electric and magnetic profiles with translational symmetry along the
y-direction, the Dirac equation is transformed into two decoupled pairs of
Schr\"odinger equations, one for each chirality of the fermion fields. Taking
trigonometric and hyperbolic profiles for the vector and scalar potentials,
respectively, we arrive at SUSY partner P\"oschl-Teller-like quantum
potentials. Restricting to the conditions of the potentials that support an
analytic zero-mode solution, we obtain a nontrivial current density in the same
plane where the electric and magnetic fields lie, but perpendicular to both of
them, indicating the possibility of realizing the Planar Hall Effect.
Furthermore, this non-vanishing current density is the sum of current densities
for the left- and right-chiralities, suggesting that the net current is a
consequence of chiral symmetry.
Re-configurable materials and meta-materials can jump between space symmetry
classes during their deformations. Here, we introduce the concept of singular
symmetry enhancement, which refers to an abrupt jump to a higher symmetry class
accompanied by an un-avoidable reduction in the number of dispersion bands of
the excitations of the material. Such phenomenon prompts closings of some of
the spectral resonant gaps along singular manifolds in a parameter space. In
this work, we demonstrate that these singular manifolds carry topological
charges. As a concrete example, we show that a deformation of an acoustic
crystal that encircles a $p11g$-symmetric configuration of the cavity
resonators results in an adiabatic cycle that carries a Chern number in the
bulk and displays Thouless pumping at the edges. The outcome is a very general
principle for recognizing or engineering topological adiabatic processes in
complex materials and meta-materials.
Time reversal and inversion symmetric materials fail to yield linear and
nonlinear responses since they possess net zero Berry curvature. However,
higher-order Hall response can be generated in these systems upon constraining
the crystalline symmetries. Motivated by the recently discovered third-order
Hall (TOH) response mediated by Berry connection polarizability, namely, the
variation the Berry connection with respect to an applied electric field, here
we investigate the existence of such Hall effect in the surface states of
hexagonal warped topological insulator (e.g., Bi$_2$Te$_3$) under the
application of electric field only. Using the semiclassical Boltzmann
formalism, we investigate the effect of tilt and hexagonal warping on the Berry
connection polarizability tensor and consequently, the TOH effect provided the
Dirac cone remains gapless. We find that the magnitude of the response
increases significantly with increasing the tilt strength and warping and
therefore, they can provide the tunability of this effect. In addition, we also
explore the effect of chemical doping on TOH response in this system.
Interestingly, we show based on the symmetry analysis, that the TOH can be the
leading-order response in this system which can directly be verified in
experiments.
We introduce interactions into two general models for quantum spin Hall
physics. Although the traditional picture is that such physics appears when the
two lower spinful bands are occupied, that is, half-filling, we show using
determinantal quantum Monte Carlo as well as from an exactly solvable model
that in the presence of strong interactions, the quarter-filled state instead
exhibits the quantum spin Hall effect at high temperature. A topological Mott
insulator is the underlying cause. The peak in the spin susceptibility is
consistent with a possible ferromagnetic state at $T=0$. The onset of such
magnetism would convert the quantum spin Hall to a quantum anomalous Hall
effect. We argue that it is the consistency with the Lieb-Schultz-Mattis
theorem\cite{lsm1,lsm2} for interacting systems with an odd number of charges
per unit cell that underlies the emergence of the quantum anomalous Hall effect
as a low-temperature symmetry-broken phase of the quantum spin Hall effect.
While such a symmetry-broken phase typically is accompanied by a gap, we find
that the interaction strength must exceed a critical value for the gap to form
using quantum Monte Carlo dynamical cluster approximation simulations. Hence,
we predict that topology can obtain in a gapless phase but only in the presence
of interactions in dispersive bands. These results are applied to recent
experiments on moir\'e systems and shown to be consistent with valley-coherent
quantum anomalous Hall physics.
We propose a scheme to implement Kitaev's honeycomb model with cold atoms,
based on a periodic (Floquet) drive, in view of realizing and probing
non-Abelian chiral spin liquids using quantum simulators. We derive the
effective Hamiltonian to leading order in the inverse-frequency expansion, and
show that the drive opens up a topological gap in the spectrum without mixing
the effective Majorana and vortex degrees of freedom. We address the challenge
of probing the physics of Majorana fermions, while having only access to the
original composite spin degrees of freedom. Specifically, we propose to detect
the properties of the chiral spin liquid phase using gap spectroscopy and edge
quenches in the presence of the Floquet drive. The resulting chiral edge
signal, which relates to the thermal Hall effect associated with neutral
Majorana currents, is found to be robust for realistically-prepared states. By
combining strong interactions with Floquet engineering, our work paves the way
for future studies of non-Abelian excitations and quantized thermal transport
using quantum simulators.
A realistic first-principle-based spin Hamiltonian is constructed for the
type-II multiferroic NiI$_2$, using a symmetry-adapted cluster expansion
method. Besides single ion anisotropy and isotropic Heisenberg terms, this
model further includes the Kitaev interaction and a biquadratic term, and can
well reproduce striking features of the experimental helical ground state, that
are, {\it e.g.}, a proper screw state, canting of rotation plane, propagation
direction and period. Using this model to build a phase diagram, it is
demonstrated that, (i) the in-plane propagation direction of
$\langle1\bar10\rangle$ is determined by the Kitaev interaction, instead of the
long-believed exchange frustrations; and (ii) the canting of rotation plane is
also dominantly determined by Kitaev interaction, rather than interlayer
couplings. Furthermore, additional Monte Carlo simulations reveal three
equivalent domains and different topological defects. Since the
ferroelectricity is induced by spins in type-II multiferroics, our work also
implies that Kitaev interaction is closely related to the multiferroicity of
NiI$_2$.
The normal state in iron chalcogenides is metallic but highly unusual, with
orbital and spin degrees of freedom partially itinerant or localized depending
on temperature, leading to many unusual features. In this work, we report on
the observations of two of such features, the orbital selective Mott phase
(OSMP) and spin nematicity, evidenced in magnetization and magnetotransport
[resistivity, Hall effect, angular magnetoresistance (AMR)] of
Fe$_{1-y}$Ni$_y$Te$_{0.65}$Se$_{0.35}$ single crystals, with $0 < y < 0.21$.
Substitution of Ni dopes crystals with electrons, what eliminates some of the
hole pockets from Fermi level, leaving only one, originating from $d_{xy}$
orbital. This leads to electron-dominated conduction at low $T$ for $y \gtrsim
0.06$. However, at high temperatures, $T \gtrsim 125 \div 178$ K, the
conduction reverses to hole-dominated. Anomalies in magnetization and
resistivity are observed at temperatures which approach high-$T$ boundary of
the electron-dominated region. Analysis of these effects suggests a link with
the appearance of the $d_{z^2}$ hole pockets at X points of the Brillouin zone
in the OSMP phase, facilitated by the localization of $d_{xy}$ orbital, as
recently reported by angular resolved photoemission experiments (Commun. Phys.
5, 29 (2022)). The low-$T$ AMR shows mixed 4-fold and 2-fold rotational
symmetry of in-plane magnetocrystalline anisotropy, with the 4-fold term the
largest at small $y$, and suppressed at intermediate $y$. These results are
consistent with the mixed stripe/bicollinear magnetic correlations at small
$y$, and suppression of stripe correlations at intermediate $y$, indicating
development of spin nematicity with increasing Ni doping, which possibly
contributes to the suppression of superconductivity.
The fermion disorder operator has been shown to reveal the entanglement
information in 1D Luttinger liquids and 2D free and interacting Fermi and
non-Fermi liquids emerging at quantum critical points(QCP). Here we study, by
means of large-scale quantum Monte Carlo simulation, the scaling behavior of
disorder operator in correlated Dirac systems. We first demonstrate the
logarithmic scaling behavior of the disorder operator at the Gross-Neveu (GN)
chiral Ising and Heisenberg QCPs, where consistent conformal field theory (CFT)
content of the GN-QCP in its coefficient is found. Then we study a 2D monopole
free deconfined quantum critical point (DQCP) realized between a quantum-spin
Hall insulator and a superconductor. Our data point to negative values of the
logarithmic coefficients such that the DQCP does not correspond to a unitary
CFT. Density matrix renormalization group calculations of the disorder operator
on a 1D DQCP model also detect emergent continuous symmetries.
We study the effects of measurements, performed with a finite density in
space, on the ground state of the one-dimensional transverse-field Ising model
at criticality. Local degrees of freedom in critical states exhibit long-range
entanglement, and as a result, local measurements can have highly nonlocal
effects. Our analytical investigation of correlations and entanglement in the
ensemble of measured states is based on properties of the Ising conformal field
theory (CFT), where measurements appear as (1+0)-dimensional defects in the
(1+1)-dimensional Euclidean spacetime. So that we can verify our predictions
using large-scale free-fermion numerics, we restrict ourselves to
parity-symmetric measurements. To describe their averaged effects analytically
we use a replica approach, and we show that the defect arising in the replica
theory is an irrelevant perturbation to the Ising CFT. Strikingly, the
asymptotic scalings of averaged correlations and entanglement entropy are
therefore unchanged relative to the ground state. In contrast, the defect
generated by postselecting on the most likely measurement outcomes is exactly
marginal. We then find that the exponent governing postmeasurement order
parameter correlations, as well as the ''effective central charge'' governing
the scaling of entanglement entropy, vary continuously with the density of
measurements in space. Our work establishes new connections between the effects
of measurements on many-body quantum states and of physical defects on
low-energy equilibrium properties.
Microswimmer suspensions in Newtonian fluids exhibit unusual macroscale
properties, such as a superfluidic behavior, which can be harnessed to perform
work at microscopic scales. Since most biological fluids are non-Newtonian,
here we study the rheology of a microswimmer suspension in a weakly
viscoelastic shear flow. At the individual level, we find that the viscoelastic
stresses generated by activity substantially modify the Jeffery orbits
well-known from Newtonian fluids. The orientational dynamics depends on the
swimmer type; especially pushers can resist flow-induced rotation and align at
an angle with the flow. To analyze its impact on bulk rheology, we study a
dilute microswimmer suspension in the presence of random tumbling and
rotational diffusion. Strikingly, swimmer activity and its elastic response in
polymeric fluids alter the orientational distribution and substantially amplify
the swimmer-induced viscosity. This suggests that pusher suspensions reach the
superfluidic regime at lower volume fractions compared to a Newtonian fluid
with identical viscosity.
We study equilibrium crystal shapes of a topological insulator (TI), a
topological crystalline insulator (TCI) protected by mirror symmetry, and a
second-order topological insulator (SOTI) protected by inversion symmetry. By
adding magnetic fields to the three-dimensional TI, we can realize the
mirror-symmetry-protected TCI and the inversion-symmetry-protected SOTI. They
each have topological boundary states in different positions: the TCI has
gapless states on the surfaces that are invariant under the symmetry operation,
and the SOTI has gapless states at the intersections between certain surfaces.
In this paper, we discuss how these boundary states affect the surface energies
and the equilibrium crystal shapes in terms of the calculations of the simple
tight-binding model by using the Wulff construction. By comparing the changes
in the shapes of the TI to that of the trivial insulator through the process of
applying the magnetic fields, we show that the presence/absence of the
topological boundary states affects the emergence of the specific facets in a
different way from the trivial insulator.
Increasing experimental evidence suggests the occurrence of filamentary
superconductivity in different (quasi) two-dimensional physical systems. In
this piece of work, we discuss the proposal that under certain circumstances,
this occurrence may be related to the competition with a phase characterized by
charge ordering in the form of charge-density waves. We provide a brief summary
of experimental evidence supporting our argument in two paradigmatic classes of
materials, namely transition metal dichalcogenides and cuprates
superconductors. We present a simple Ginzburg-Landau two-order-parameters model
as a starting point to address the study of such competition. We finally
discuss the outcomes of a more sophisticated model, already presented in the
literature and encoding the presence of impurities, and how it can be further
improved in order to really address the interplay between charge-density waves
and superconductivity and the possible occurrence of filamentary
superconductivity at the domain walls between different charge-ordered regions.
Nontrivial interacting phases can emerge in elementary materials. As a prime
example, continuing advances in device quality have facilitated the observation
of a variety of spontaneous quantum Hall-like states, a cascade of Stoner-like
magnets, and an unconventional superconductor in bilayer graphene. Its natural
extension, rhombohedral trilayer graphene is predicted to be even more
susceptible to interactions given its even flatter low-energy bands and larger
winding number. Theoretically, five spontaneous quantum Hall phases have been
proposed to be candidate ground states. Here, we provide transport evidence for
observing four of the five competing ordered states in interaction-maximized,
dually-gated, rhombohedral trilayer graphene. In particular, at vanishing but
finite magnetic fields, two states with Chern numbers 3 and 6 can be stabilized
at elevated and low electric fields, respectively, and both exhibit clear
magnetic hysteresis. We also reveal that the quantum Hall ferromagnets of the
zeroth Landau level are ferroelectrics with spontaneous layer polarizations
even at zero electric field, as evidenced by electric hysteresis. Our findings
exemplify the possible birth of rich interacting electron physics in a simple
elementary material.
An axion insulator is a three-dimensional (3D) topological insulator (TI), in
which the bulk maintains the time-reversal symmetry or inversion symmetry but
the surface states are gapped by surface magnetization. The axion insulator
state has been observed in molecular beam epitaxy (MBE)-grown magnetically
doped TI sandwiches and exfoliated intrinsic magnetic TI MnBi2Te4 flakes with
an even number layer. All these samples have a thickness of ~10 nm, near the
2D-to-3D boundary. The coupling between the top and bottom surface states in
thin samples may hinder the observation of quantized topological
magnetoelectric response. Here, we employ MBE to synthesize magnetic TI
sandwich heterostructures and find that the axion insulator state persists in a
3D sample with a thickness of ~106 nm. Our transport results show that the
axion insulator state starts to emerge when the thickness of the middle undoped
TI layer is greater than ~3 nm. The 3D hundred-nanometer-thick axion insulator
provides a promising platform for the exploration of the topological
magnetoelectric effect and other emergent magnetic topological states, such as
the high-order TI phase.

Date of feed: Thu, 29 Jun 2023 00:30:00 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+) **Electrical contact properties between Yb and few-layer WS$_2$. (arXiv:2306.15689v1 [cond-mat.mtrl-sci])**

Shihao Ju, Lipeng Qiu, Jian Zhou, Binxi Liang, Wenfeng Wang, Taotao Li, Jian Chen, Xinran Wang, Yi Shi, Songlin Li

**A nanogapped hysteresis-free field-effect transistor. (arXiv:2306.15690v1 [cond-mat.mes-hall])**

Jiachen Tang, Luhao Liu, Yinjiang Shao, Xinran Wang, Yi Shi, Songlin Li

**Clean BN encapsulated 2D FETs with lithography compatible contacts. (arXiv:2306.15691v1 [cond-mat.mes-hall])**

Binxi Liang, Anjian Wang, Jian Zhou, Shihao Ju, Jian Chen, Kenji Watanabe, Takashi Taniguchi, Yi Shi, Songlin Li

**Spin-circuit representation of spin pumping into topological insulators and determination of giant spin Hall angle and inverse spin Hall voltages. (arXiv:2306.15699v1 [cond-mat.mes-hall])**

Kuntal Roy

**Formation of droplets of the order parameter and superconductivity in inhomogeneous Fermi-Bose mixtures (Brief review). (arXiv:2306.15770v1 [cond-mat.mes-hall])**

M.Yu. Kagan, S.V. Aksenov, A.V. Turlapov, R.Sh. Ikhsanov, K.I. Kugel, E.A. Mazur, E.A. Kuznetsov, V.M. Silkin, E.A. Burovski

**Pressure dependence of intra- and interlayer excitons in 2H-MoS$_2$ bilayers. (arXiv:2306.15780v1 [cond-mat.mes-hall])**

Paul Steeger, Jan-Hauke Graalmann, Robert Schmidt, Ilya Kupenko, Carmen Sanchez-Valle, Philipp Marauhn, Thorsten Deilmann, Steffen Michaelis de Vasconcellos, Michael Rohlfing, Rudolf Bratschitsch

**Kibble-Zurek mechanism of Ising domains. (arXiv:2306.15821v1 [cond-mat.stat-mech])**

Kai Du, Xiaochen Fang, Choongjae Won, Chandan De, Fei-ting Huang Fernando J. Gomez-Ruiz, Adolfo Del Campo, Sang-Wook Cheong

**Sterically Induced Binding Selectivity of Single m-Terphenyl Isocyanide Ligands. (arXiv:2306.15840v1 [cond-mat.mes-hall])**

Liya Bi, Sasawat Jamnuch, Amanda Chen, Alexandria Do, Krista P. Balto, Zhe Wang, Qingyi Zhu, Yufei Wang, Yanning Zhang, Andrea R. Tao, Tod A. Pascal, Joshua S. Figueroa, Shaowei Li

**Coupling and decoupling of bilayer graphene monitored by electron energy loss spectroscopy. (arXiv:2306.15849v1 [cond-mat.mtrl-sci])**

Yung-Chang Lin, Amane Motoyama, Pablo Solis-Fernandez, Rika Matsumoto, Hiroki Ago, Kazu Suenaga

**Chern insulating state with double-$Q$ ordering wave vectors at the Brillouin zone boundary. (arXiv:2306.15854v1 [cond-mat.str-el])**

Satoru Hayami

**Dissipative Spin-wave Diode and Nonreciprocal Magnonic Amplifier. (arXiv:2306.15916v1 [cond-mat.mes-hall])**

Ji Zou, Stefano Bosco, Even Thingstad, Jelena Klinovaja, Daniel Loss

**Dyck Paths and Topological Quantum Computation. (arXiv:2306.16062v1 [quant-ph])**

Vivek Kumar Singh, Akash Sinha, Pramod Padmanabhan, Indrajit Jana

**MoRe Electrodes with 10-nm Nanogaps for Electrical Contact to Atomically Precise Graphene Nanoribbons. (arXiv:2306.16070v1 [cond-mat.mes-hall])**

Damian Bouwmeester, Talieh S. Ghiasi, Gabriela Borin Barin, Klaus Müllen, Pascal Ruffieux, Roman Fasel, Herre S.J. van der Zant

**Spin-resolved spectroscopic evidence for spinarons in Co adatoms. (arXiv:2306.16084v1 [cond-mat.str-el])**

Felix Friedrich, Artem Odobesko, Juba Bouaziz, Samir Lounis, Matthias Bode

**Strong coupling of monolayer WS2 excitons and surface plasmon polaritons in a planar Ag/WS2 hybrid structure. (arXiv:2306.16107v1 [physics.optics])**

Nicolas Zorn Morales, Daniel Steffen Rühl, Sergey Sadofev, Giovanni Ligorio, Emil List-Kratochvil, Günter Kewes, Sylke Blumstengel

**Quantum-information theory of magnetic field influence on circular dots with different boundary conditions. (arXiv:2306.16114v1 [quant-ph])**

H. Shafeekali, O. Olendski

**Accurate force-field methodology capturing atomic reconstructions in transition metal dichalcogenide moir\'e systems. (arXiv:2306.16124v1 [cond-mat.mtrl-sci])**

Carl Emil Mørch Nielsen, Miguel da Cruz, Abderrazak Torche, Gabriel Bester

**Phase diagram of the chiral SU(3) antiferromagnet on the kagome lattice. (arXiv:2306.16192v1 [cond-mat.str-el])**

Yi Xu, Sylvain Capponi, Ji-Yao Chen, Laurens Vanderstraeten, Juraj Hasik, Andriy H. Nevidomskyy, Matthieu Mambrini, Karlo Penc, Didier Poilblanc

**Non-local transport signatures of topological superconductivity in a phase-biased planar Josephson junction. (arXiv:2306.16232v1 [cond-mat.mes-hall])**

D. Kuiri, M. P. Nowak

**The dynamical structure factor of the SU(4) algebraic spin liquid on the honeycomb lattice. (arXiv:2306.16242v1 [cond-mat.str-el])**

Dániel Vörös, Karlo Penc

**Roadmap towards Majorana qubits and nonabelian physics in quantum dot-based minimal Kitaev chains. (arXiv:2306.16289v1 [cond-mat.mes-hall])**

Athanasios Tsintzis, Rubén Seoane Souto, Karsten Flensberg, Jeroen Danon, Martin Leijnse

**Electronic Landscape of Kagome Superconductors $\textit{A}$V$_{3}$Sb$_{5}$ ($\textit{A}$ = K, Rb, Cs): A Perspective from Angle-Resolved Photoemission Spectroscopy. (arXiv:2306.16343v1 [cond-mat.supr-con])**

Yong Hu, Xianxin Wu, Andreas P. Schnyder, Ming Shi

**Dirac materials in parallel non-uniform electromagnetic fields generated by SUSY: A new class of chiral Planar Hall Effect?. (arXiv:2306.16399v1 [hep-th])**

Julio Cesar Pérez-Pedraza, Juan D. García-Muñoz, A. Raya

**Pumping with Symmetry. (arXiv:2306.16401v1 [cond-mat.mtrl-sci])**

Julio Andrés Iglesias Martínez, Muamer Kadic, Vincent Laude, Emil Prodan

**Third-order Hall effect in the surface states of a topological insulator. (arXiv:2209.06867v2 [cond-mat.mes-hall] UPDATED)**

Tanay Nag, Sanjib Kumar Das, Chuanchang Zeng, Snehasish Nandy

**1/4 is the new 1/2: Interaction-induced Unification of Quantum Anomalous and Spin Hall Effects. (arXiv:2210.11486v4 [cond-mat.mes-hall] UPDATED)**

Peizhi Mai, Jinchao Zhao, Benjamin E. Feldman, Philip W. Phillips

**Engineering and probing non-Abelian chiral spin liquids using periodically driven ultracold atoms. (arXiv:2211.09777v3 [cond-mat.quant-gas] UPDATED)**

Bo-Ye Sun, Nathan Goldman, Monika Aidelsburger, Marin Bukov

**Realistic Spin Model for Multiferroic NiI$_2$. (arXiv:2211.14416v3 [cond-mat.str-el] UPDATED)**

Xuanyi Li, Changsong Xu, Boyu Liu, Xueyang Li, L. Bellaiche, Hongjun Xiang

**Orbital-selective Mott phase and spin nematicity in Ni-substituted FeTe$_{0.65}$Se$_{0.35}$ single crystals. (arXiv:2211.15189v2 [cond-mat.supr-con] UPDATED)**

Marta Z. Cieplak, I. Zajcewa, A. Lynnyk, K. M. Kosyl, D. J. Gawryluk

**Fermion disorder operator at Gross-Neveu and deconfined quantum criticalities. (arXiv:2212.11821v2 [cond-mat.str-el] UPDATED)**

Zi Hong Liu, Weilun Jiang, Bin-Bin Chen, Junchen Rong, Meng Cheng, Kai Sun, Zi Yang Meng, Fakher F. Assaad

**Nonlocality and entanglement in measured critical quantum Ising chains. (arXiv:2301.08268v2 [cond-mat.stat-mech] UPDATED)**

Zack Weinstein, Rohith Sajith, Ehud Altman, Samuel J. Garratt

**Orientational dynamics and rheology of active suspensions in weakly viscoelastic flows. (arXiv:2303.15241v2 [cond-mat.soft] UPDATED)**

Akash Choudhary, Sankalp Nambiar, Holger Stark

**Effects of first- and second-order topological phases on equilibrium crystal shapes. (arXiv:2304.08150v2 [cond-mat.mes-hall] UPDATED)**

Yutaro Tanaka, Shuichi Murakami

**Charge-Density Waves vs. Superconductivity: Some Results and Future Perspectives. (arXiv:2305.03404v2 [cond-mat.supr-con] UPDATED)**

Giulia Venditti, Sergio Caprara

**Ferroelectric and anomalous quantum Hall states in bare rhombohedral trilayer graphene. (arXiv:2305.04950v2 [cond-mat.mes-hall] UPDATED)**

Felix Winterer, Fabian R. Geisenhof, Noelia Fernandez, Anna M. Seiler, Fan Zhang, R. Thomas Weitz

**Axion Insulator State in Hundred-Nanometer-Thick Magnetic Topological Insulator Sandwich Heterostructures. (arXiv:2306.13016v3 [cond-mat.mes-hall] UPDATED)**

Deyi Zhuo, Zi-Jie Yan, Zi-Ting Sun, Ling-Jie Zhou, Yi-Fan Zhao, Ruoxi Zhang, Ruobing Mei, Hemian Yi, Ke Wang, Moses H. W. Chan, Chao-Xing Liu, K. T. Law, Cui-Zu Chang

Found 8 papers in prb We present our studies on polycrystalline samples of fluorine doped ${\mathrm{LaMnO}}_{3}$ (${\mathrm{LaMnO}}_{3−y}{\mathrm{F}}_{y}$). ${\mathrm{LaMnO}}_{3−y}{\mathrm{F}}_{y}$ exhibits remarkable magnetic and electrical properties. It shows ferromagnetic and metallic behavior with a high Curie tempe… In this study, we investigate the weak localization (WL) and weak antilocalization (WAL) effects in twisted bilayer graphene positioned on a hexagonal boron nitride substrate. The bottom graphene layer aligns with the hexagonal boron nitride. The top layer of the system features a Dirac cone with a … The anomalous Hall effect and the closely related polar Kerr effect are among the most direct evidence of chiral Cooper pairing in some superconductors. While it has been known that disorder or multiband pairing is typically needed for these effects to manifest, there is a lack of direct real-space … Topological excitonic insulators combine topological edge states and spontaneous exciton condensation, with dual functionality of topological insulators and excitonic insulators. Yet, they are very rare and little is known about their formation. In this work, we find that a mechanism dubbed as parit… Extended reservoirs provide a framework for capturing macroscopic, continuum environments, such as metallic electrodes driving a current through a nanoscale contact, impurity, or material. We examine the application of this approach to periodically driven systems, specifically in the context of quan… The semimetal bismuth displays a multifaceted nonlinear terahertz response, which is studied by two-dimensional terahertz (2D-THz) spectroscopy. Nonperturbative excitation drives intra- and interband electron transitions close to the narrow band gaps at the $L$ points of the Brillouin zone, giving rise to pump-probe signals and high-harmonic generation. Preferential excitation in two of the six $L$ valleys generates an anisotropic carrier distribution across the Brillouin zone, causing a hexagonal azimuthal angular dependence of the pump-probe signal. The concomitant symmetry reduction allows excitation of coherent phonon wavepackets along back-folded phonon coordinates. Time reversal and inversion symmetric materials fail to yield linear and nonlinear responses since they possess net zero Berry curvature. However, higher-order Hall response can be generated in these systems upon constraining the crystalline symmetries. Motivated by the recently discovered third-ord… Studying spin-$\frac{1}{2}$ fermions coupled to ${\mathbb{Z}}_{2}$ gauge fields on the square lattice, we show how a spatial modulation of the fermion hopping amplitude allows for the realization of various obstructed atomic insulators that host higher-order band topology. Including the effect of qu…

Date of feed: Thu, 29 Jun 2023 03:16:57 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+) **Ferromagnetism and metal-insulator transition in F-doped ${\mathrm{LaMnO}}_{3}$**

Ekta Yadav, Pramod Ghising, K. P. Rajeev, and Z. Hossain

Author(s): Ekta Yadav, Pramod Ghising, K. P. Rajeev, and Z. Hossain

[Phys. Rev. B 107, 214446] Published Wed Jun 28, 2023

**Weak localization and antilocalization in twisted bilayer graphene**

Hongyi Yan and Haiwen Liu

Author(s): Hongyi Yan and Haiwen Liu

[Phys. Rev. B 107, 224205] Published Wed Jun 28, 2023

**Impact of random impurities on the anomalous Hall effect in chiral superconductors**

Hao-Tian Liu, Weipeng Chen, and Wen Huang

Author(s): Hao-Tian Liu, Weipeng Chen, and Wen Huang

[Phys. Rev. B 107, 224517] Published Wed Jun 28, 2023

**Robust high-temperature topological excitonic insulator of transition-metal carbide MXenes**

Shan Dong and Yuanchang Li

Author(s): Shan Dong and Yuanchang Li

[Phys. Rev. B 107, 235147] Published Wed Jun 28, 2023

**Transport in a periodically driven tilted lattice via the extended reservoir approach: Stability criterion for recovering the continuum limit**

Bitan De, Gabriela Wójtowicz, Jakub Zakrzewski, Michael Zwolak, and Marek M. Rams

Author(s): Bitan De, Gabriela Wójtowicz, Jakub Zakrzewski, Michael Zwolak, and Marek M. Rams

[Phys. Rev. B 107, 235148] Published Wed Jun 28, 2023

**Ultrafast carrier dynamics and symmetry reduction in bismuth by nonperturbative optical excitation in the terahertz range**

Matthias Runge, Ahmed Ghalgaoui, Isabel Gonzalez-Vallejo, Fabian Thiemann, Michael Horn-von Hoegen, Klaus Reimann, Michael Woerner, and Thomas Elsaesser

Author(s): Matthias Runge, Ahmed Ghalgaoui, Isabel Gonzalez-Vallejo, Fabian Thiemann, Michael Horn-von Hoegen, Klaus Reimann, Michael Woerner, and Thomas Elsaesser

[Phys. Rev. B 107, 245140] Published Wed Jun 28, 2023

**Third-order Hall effect in the surface states of a topological insulator**

Tanay Nag, Sanjib Kumar Das, Chuanchang Zeng, and Snehasish Nandy

Author(s): Tanay Nag, Sanjib Kumar Das, Chuanchang Zeng, and Snehasish Nandy

[Phys. Rev. B 107, 245141] Published Wed Jun 28, 2023

**Obstructed atomic insulators and superfluids of fermions coupled to ${\mathbb{Z}}_{2}$ gauge fields**

Bhandaru Phani Parasar and Vijay B. Shenoy

Author(s): Bhandaru Phani Parasar and Vijay B. Shenoy

[Phys. Rev. B 107, 245142] Published Wed Jun 28, 2023

Found 2 papers in prl Interferometry is a prime technique for modern precision measurements. Atoms, unlike light, have significant interactions with electric, magnetic, and gravitational fields, making their use in interferometric applications particularly versatile. Here, we demonstrate atom interferometry to image opti… Nuclear magnetic resonance spectroscopy offers strong evidence that YPtBi can exhibit topological superconductivity, a property that could be harnessed to build quantum computers.

Date of feed: Thu, 29 Jun 2023 03:16:59 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+) **Atom Interferometric Imaging of Differential Potentials Using an Atom Laser**

M. E. Mossman, Ryan A. Corbin, Michael McNeil Forbes, and P. Engels

Author(s): M. E. Mossman, Ryan A. Corbin, Michael McNeil Forbes, and P. Engels

[Phys. Rev. Lett. 130, 263402] Published Wed Jun 28, 2023

**Antiferromagnetic Spin Fluctuations and Unconventional Superconductivity in Topological Superconductor Candidate YPtBi Revealed by $^{195}\mathrm{Pt}$-NMR**

Y. Z. Zhou, J. Chen, Z. X. Li, J. Luo, J. Yang, Y. F. Guo, W. H. Wang, R. Zhou, and Guo-qing Zheng

Author(s): Y. Z. Zhou, J. Chen, Z. X. Li, J. Luo, J. Yang, Y. F. Guo, W. H. Wang, R. Zhou, and Guo-qing Zheng

[Phys. Rev. Lett. 130, 266002] Published Wed Jun 28, 2023

Found 3 papers in nano-lett

Date of feed: Thu, 29 Jun 2023 01:07:21 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+) **[ASAP] Side-Chain-Dependent Functional Intercalations in Graphene Oxide Membranes for Selective Water and Ion Transport**

Kecheng Guan, Zhaohuan Mai, Siyu Zhou, Shang Fang, Zhan Li, Ping Xu, Yu-Hsuan Chiao, Mengyang Hu, Pengfei Zhang, Guorong Xu, Keizo Nakagawa, and Hideto MatsuyamaNano LettersDOI: 10.1021/acs.nanolett.3c01541

**[ASAP] Trion Formation Resolves Observed Peak Shifts in the Optical Spectra of Transition-Metal Dichalcogenides**

Thomas Sayer, Yusef R. Farah, Rachelle Austin, Justin Sambur, Amber T. Krummel, and Andrés Montoya-CastilloNano LettersDOI: 10.1021/acs.nanolett.3c01342

**[ASAP] Experimental Demonstration of a Magnetically Induced Warping Transition in a Topological Insulator Mediated by Rare-Earth Surface Dopants**

Beatriz Muñiz Cano, Yago Ferreiros, Pierre A. Pantaleón, Ji Dai, Massimo Tallarida, Adriana I. Figueroa, Vera Marinova, Kevin García-Díez, Aitor Mugarza, Sergio O. Valenzuela, Rodolfo Miranda, Julio Camarero, Francisco Guinea, Jose Angel Silva-Guillén, and Miguel A. ValbuenaNano LettersDOI: 10.1021/acs.nanolett.3c00587

Found 2 papers in acs-nano

Date of feed: Wed, 28 Jun 2023 21:20:59 GMT**Search terms: **(topolog[a-z]+)|(graphit[a-z]+)|(rhombohedr[a-z]+)|(graphe[a-z]+)|(chalcog[a-z]+)|(landau)|(weyl)|(dirac)|(STM)|(scan[a-z]+ tunne[a-z]+ micr[a-z]+)|(scan[a-z]+ tunne[a-z]+ spectr[a-z]+)|(scan[a-z]+ prob[a-z]+ micr[a-z]+)|(MoS.+\d+|MoS\d+)|(MoSe.+\d+|MoSe\d+)|(MoTe.+\d+|MoTe\d+)|(WS.+\d+|WS\d+)|(WSe.+\d+|WSe\d+)|(WTe.+\d+|WTe\d+)|(Bi\d+Rh\d+I\d+|Bi.+\d+.+Rh.+\d+.+I.+\d+.+)|(BiTeI)|(BiTeBr)|(BiTeCl)|(ZrTe5|ZrTe.+5)|(Pt2HgSe3|Pt.+2HgSe.+3)|(jacuting[a-z]+) **[ASAP] Ultra-Wideband Mid-Infrared Chalcogenide Suspended Nanorib Waveguide Gas Sensors with Exceptionally High External Confinement Factor beyond Free-Space**

Mingquan Pi, Chuantao Zheng, Huan Zhao, Zihang Peng, Gangyun Guan, Jialin Ji, Yijun Huang, Yuting Min, Lei Liang, Fang Song, Xue Bai, Yu Zhang, Yiding Wang, and Frank K. TittelACS NanoDOI: 10.1021/acsnano.3c02699

**[ASAP] Cascaded Logic Gates Based on High-Performance Ambipolar Dual-Gate WSe _{2} Thin Film Transistors**

Xintong Li, Peng Zhou, Xuan Hu, Ethan Rivers, Kenji Watanabe, Takashi Taniguchi, Deji Akinwande, Joseph S. Friedman, and Jean Anne C. Incorvia

ACS Nano

DOI: 10.1021/acsnano.3c03932