We study transient dynamics in a two-dimensional system of interacting Dirac fermions subject to a quenched drive with circularly polarized light. In the absence of interactions, the drive opens a gap at the Dirac point in the quasienergy spectrum, inducing nontrivial band topology. We investigate t...

[Phys. Rev. Lett. 121, 036801] Published Mon Jul 16, 2018

]]>Strain in a semiconductor quantum well spatially modulates the electron population, leading to a valley superlattice.

[Phys. Rev. Lett. 121, 036802] Published Mon Jul 16, 2018

]]>Inducing superconductivity in a topological insulator can lead to novel quantum effects. However, experimental approaches to turn a topological insulator into a superconductor are limited. Here, we report on superconductivity in topological insulator ${\mathrm{Bi}}_{0.91}{\mathrm{Sb}}_{0.09}$ induced via focused ion-beam deposit...

[Phys. Rev. Lett. 121, 037001] Published Mon Jul 16, 2018

]]>Thermally injected pure spin current phenomena have been investigated in $\mathrm{Bi}/{\mathrm{Y}}_{3}{\mathrm{Fe}}_{5}{\mathrm{O}}_{12}$ and $\mathrm{Bi}/\mathrm{Ag}/{\mathrm{Y}}_{3}{\mathrm{Fe}}_{5}{\mathrm{O}}_{12}$ structures at room temperature. We show that although pure spin current has been injected into the Bi layer and the $\mathrm{Bi}/\mathrm{Ag}$ bilayer, there is little detectable signal of spin-to-charge conversion, e...

[Phys. Rev. Lett. 121, 037201] Published Mon Jul 16, 2018

]]>Spin-torque-biased magnetic dynamics in an easy-plane ferromagnet (EPF) is theoretically studied in the presence of a weak in-plane anisotropy. While this anisotropy spoils U(1) symmetry, thereby quenching the conventional spin superfluidity, we show that the system instead realizes a close analog o...

[Phys. Rev. Lett. 121, 037202] Published Mon Jul 16, 2018

]]>A primary limitation of the intensively researched polaritonic systems compared to their atomic counterparts for the study of strongly correlated phenomena and many-body physics is their relatively weak two-particle interactions compared to disorder. Here, we show how new opportunities to enhance su...

[Phys. Rev. Lett. 121, 037401] Published Mon Jul 16, 2018

]]>In a Weyl superconductor, Landau levels and a vortex lattice may coexist.

[Phys. Rev. Lett. 121, 037701] Published Mon Jul 16, 2018

]]>We develop an analytic theory for the recently demonstrated Josephson junction laser [M. C. Cassidy *et al.*, Science **355**, 939 (2017)]. By working in the time-domain representation (rather than the frequency domain), a single nonlinear equation is obtained for the dynamics of the device, which is ful...

[Phys. Rev. Lett. 121, 027004] Published Fri Jul 13, 2018

]]>We performed high-pressure x-ray diffraction (XRD), Raman, and transport measurements combined with first-principles calculations to investigate the behavior of tin diselenide (${\mathrm{SnSe}}_{2}$) under compression. The obtained single-crystal XRD data indicate the formation of a $(1/3,1/3,0)$-type superlattice ab...

[Phys. Rev. Lett. 121, 027003] Published Thu Jul 12, 2018

]]>Motivated by recent experiments on Kondo insulators, we theoretically study quantum oscillations from disorder-induced in-gap states in small-gap insulators. By solving a non-Hermitian Landau level problem that incorporates the imaginary part of electron’s self-energy, we show that the oscillation p...

[Phys. Rev. Lett. 121, 026403] Published Wed Jul 11, 2018

]]>A versatile and efficient variational approach is developed to solve in- and out-of-equilibrium problems of generic quantum spin-impurity systems. Employing the discrete symmetry hidden in spin-impurity models, we present a new canonical transformation that completely decouples the impurity and bath...

[Phys. Rev. Lett. 121, 026805] Published Wed Jul 11, 2018

]]>We report the experimental observation of commensurability oscillations (COs) in 1D graphene superlattices. The widely tunable periodic potential modulation in hBN-encapsulated graphene is generated via the interplay of nanopatterned few-layer graphene acting as a local bottom gate and a global Si b...

[Phys. Rev. Lett. 121, 026806] Published Wed Jul 11, 2018

]]>Topological insulators are promising candidates for optically driven spintronic devices, because photoexcitation of spin polarized surface states is governed by angular momentum selection rules. We carry out femtosecond midinfrared spectroscopy on thin films of the topological insulator ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{2}\mathrm{Se}$, wh...

[Phys. Rev. Lett. 121, 026807] Published Wed Jul 11, 2018

]]>Bulk/boundary correspondence is shown to exist in non-Hermitian models through the use of biorthogonal quantum mechanics.

[Phys. Rev. Lett. 121, 026808] Published Wed Jul 11, 2018

]]>We propose a mechanism whereby disorder can enhance the transition temperature ${T}_{c}$ of an unconventional superconductor with pairing driven by exchange of spin fluctuations. The theory is based on a self-consistent real space treatment of pairing in the disordered one-band Hubbard model. It has been d...

[Phys. Rev. Lett. 121, 027002] Published Wed Jul 11, 2018

]]>We theoretically investigate pumping of phonons by the dynamics of a magnetic film into a nonmagnetic contact. The enhanced damping due to the loss of energy and angular momentum shows interference patterns as a function of the resonance frequency and magnetic film thickness that cannot be described...

[Phys. Rev. Lett. 121, 027202] Published Wed Jul 11, 2018

]]>Quantum shot noise probes the dynamics of charge transfers through a quantum conductor, reflecting whether quasiparticles flow across the conductor in a steady stream, or in syncopated bursts. We have performed high-sensitivity shot noise measurements in a quantum dot obtained in a silicon metal-oxi...

[Phys. Rev. Lett. 121, 027701] Published Wed Jul 11, 2018

]]>We report the measurement of the third moment of current fluctuations in a short metallic wire at low temperature. The data are deduced from the statistics of voltage fluctuations across the conductor using a careful determination of environmental contributions. Our results at low bias agree very we...

[Phys. Rev. Lett. 121, 027702] Published Wed Jul 11, 2018

]]>We study the structural, electronic, and vibrational properties of single-layer $1T\text{\u2212}{\mathrm{NbSe}}_{2}$ from first principles. Within the generalized gradient approximation, the $1T$ polytype is highly unstable with respect to the $2H$. The density functional theory with the Hubbard $U$ method improves the stability of ...

[Phys. Rev. Lett. 121, 026401] Published Tue Jul 10, 2018

]]>Flexible long period moiré superlattices form in two-dimensional van der Waals crystals containing layers that differ slightly in lattice constant or orientation. In this Letter we show theoretically that isolated flat moiré bands described by generalized triangular lattice Hubbard models are presen...

[Phys. Rev. Lett. 121, 026402] Published Tue Jul 10, 2018

]]>We study sound in a single-channel one-dimensional quantum liquid. In contrast to classical fluids, instead of a single sound mode we find two modes of density oscillations. The speeds at which these two sound modes propagate are nearly equal, with the difference that scales linearly with the small ...

[Phys. Rev. Lett. 121, 026803] Published Tue Jul 10, 2018

]]>We derive a connection between the intrinsic tribological properties and the electronic properties of a solid interface. In particular, we show that the adhesion and frictional forces are dictated by the electronic charge redistribution occurring due to the relative displacements of the two surfaces...

[Phys. Rev. Lett. 121, 026804] Published Tue Jul 10, 2018

]]>We use spin-polarized scanning tunneling microscopy to demonstrate that Ho atoms on magnesium oxide exhibit a coercive field of more than 8 T and magnetic bistability for many minutes, both at 35 K. The first spontaneous magnetization reversal events are recorded at 45 K, for which the metastable st...

[Phys. Rev. Lett. 121, 027201] Published Tue Jul 10, 2018

]]>We study theoretically the nonreciprocal charge transport in two-dimensional noncentrosymmetric superconductors with the Rashba spin-orbit interaction. The resistivity $R$ depends on the current $I$ linearly under the external magnetic field $B$, i.e., $R={R}_{0}(1+\gamma BI)$, which is called the magnetochiral anisot...

[Phys. Rev. Lett. 121, 026601] Published Mon Jul 09, 2018

]]>We show that novel low temperature properties of bulk ${\mathrm{SmB}}_{6}$, including the sudden growth of the de Haas–van Alphen (dHvA) amplitude (and heat capacity) at millikelvin temperatures and a previously unreported linear-in-temperature bulk electrical conductivity at liquid helium temperatures, signal the ...

[Phys. Rev. Lett. 121, 026602] Published Mon Jul 09, 2018

]]>A wide variety of two-dimensional electron systems allow for independent control of the total and relative charge density of two-component fractional quantum Hall (FQH) states. In particular, a recent experiment on bilayer graphene (BLG) observed a continuous transition between a compressible and in...

[Phys. Rev. Lett. 121, 026603] Published Mon Jul 09, 2018

]]>Heat transport studies of fractional quantum Hall systems provide evidence for a new phase of matter with potential applications in fault-tolerant quantum computation.

[Phys. Rev. Lett. 121, 026801] Published Mon Jul 09, 2018

]]>We study dephasing in an electronic Mach-Zehnder (MZ) interferometer based on quantum Hall edge states by a micrometer-sized Ohmic contact embedded in one of its arms. We find that at the filling factor $\nu =1$, as well as in the case where an Ohmic contact is connected to a MZ interferometer by a quant...

[Phys. Rev. Lett. 121, 026802] Published Mon Jul 09, 2018

]]>We present the strain and temperature dependence of an anomalous nematic phase in optimally doped ${\mathrm{BaFe}}_{2}(\mathrm{As},\mathrm{P}{)}_{2}$. Polarized ultrafast optical measurements reveal broken fourfold rotational symmetry in a temperature range above ${T}_{c}$ in which bulk probes do not detect a phase transition. Using ultrafast m...

[Phys. Rev. Lett. 121, 027001] Published Mon Jul 09, 2018

]]>Previous studies showed that, as ferroelectric films become thinner, their Curie temperature (${T}_{c}$) and polarization below ${T}_{c}$ both typically decrease. In contrast, a recent experiment [Chang *et al.*, Science **353**, 274 (2016)] observed that atomic-thick SnTe films have a higher ${T}_{c}$ than their bulk counter...

[Phys. Rev. Lett. 121, 027601] Published Mon Jul 09, 2018

]]>We present numerical evidence that most two-dimensional surface states of a bulk topological superconductor (TSC) sit at an integer quantum Hall plateau transition. We study TSC surface states in class CI with quenched disorder. Low-energy (finite-energy) surface states were expected to be criticall...

[Phys. Rev. Lett. 121, 016802] Published Fri Jul 06, 2018

]]>We report the observation of the intrinsic dampinglike spin-orbit torque (SOT) arising from the Berry curvature in metallic-$\text{magnet}/{\mathrm{CuO}}_{x}$ heterostructures. We show that a robust dampinglike SOT, an order of magnitude larger than a fieldlike SOT, is generated in the heterostructure despite the absence ...

[Phys. Rev. Lett. 121, 017202] Published Fri Jul 06, 2018

]]>Out of equilibrium phenomena are a major issue of modern physics. In particular, correlated materials such as Mott insulators experience fascinating long-lived exotic states under a strong electric field. Yet, the origin of their destabilization by the electric field is not elucidated. Here we prese...

[Phys. Rev. Lett. 121, 016601] Published Tue Jul 03, 2018

]]>Out-of-time-ordered (OTO) correlators have developed into a central concept quantifying quantum information transport, information scrambling, and quantum chaos. In this Letter, we show that such an OTO correlator can also be used to dynamically detect equilibrium as well as nonequilibrium phase tra...

[Phys. Rev. Lett. 121, 016801] Published Tue Jul 03, 2018

]]>We study a 2D exchange model with a weak static random field on lattices containing over ${10}^{8}$ spins. Ferromagnetic correlations persist on the Imry-Ma scale inversely proportional to the random-field strength and decay exponentially at greater distances. We find that the average energy of the correla...

[Phys. Rev. Lett. 121, 017201] Published Tue Jul 03, 2018

]]>The shift current (SHC) has been accepted as the primary mechanism of the bulk photovoltaic effect (BPVE) in ferroelectrics, which is much different from the typical $p\text{\u2212}n$ junction-based photovoltaic mechanism in heterogeneous materials. In the present work, we use first-principles calculations to inv...

[Phys. Rev. Lett. 121, 017402] Published Tue Jul 03, 2018

]]>We experimentally report a surprising linewidth narrowing of the direct exitonic $1\text{\hspace{0.17em}}\text{\hspace{0.17em}}s$ heavy-hole transition in a type-II quantum well system. This narrowing, which builds up on a pico- to nanosecond timescale, causes a transient enhanced absorption at the spectral peak position of the excitonic reso...

[Phys. Rev. Lett. 121, 017401] Published Mon Jul 02, 2018

]]>Tunneling of electrons into a two-dimensional electron system is known to exhibit an anomaly at low bias, in which the tunneling conductance vanishes due to a many-body interaction effect. Recent experiments have measured this anomaly between two copies of the half-filled Landau level as a function ...

[Phys. Rev. Lett. 120, 266601] Published Fri Jun 29, 2018

]]>Inversion-symmetric materials are forbidden to show an overall spin texture in their band structure in the presence of time-reversal symmetry. However, in van der Waals materials which lack inversion symmetry within a single layer, it has been proposed that a layer-dependent spin texture can arise l...

[Phys. Rev. Lett. 120, 266801] Published Fri Jun 29, 2018

]]>We explore the second order bilinear magnetoelectric resistance (BMER) effect in the $d$-electron-based two-dimensional electron gas $(2\mathrm{DEG})$ at the ${\mathrm{SrTiO}}_{3}(111)$ surface. We find evidence of a spin-split band structure with the archetypal spin-momentum locking of the Rashba effect for the in-plane compon...

[Phys. Rev. Lett. 120, 266802] Published Fri Jun 29, 2018

]]>We report an inelastic neutron scattering study on the spin resonance in the bilayer iron-based superconductor ${\mathrm{CaKFe}}_{4}{\mathrm{As}}_{4}$. In contrast to its quasi-two-dimensional electron structure, three strongly $L$-dependent modes of spin resonance are found below ${T}_{c}=35\text{\hspace{0.17em}}\text{\hspace{0.17em}}\mathrm{K}$. The mode energies are below and linearly...

[Phys. Rev. Lett. 120, 267003] Published Fri Jun 29, 2018

]]>Owing to the broken translational symmetry at dislocations, a strain gradient naturally exists around the dislocation cores and can significantly influence the electrical and mechanical properties. We use aberration corrected scanning transmission electron microscopy to directly measure the flexoele...

[Phys. Rev. Lett. 120, 267601] Published Fri Jun 29, 2018

]]>We theoretically study the effects of electron-electron interaction in twisted bilayer graphene in a transverse dc electric field. When the twist angle is not very small, the electronic spectrum of the bilayer consists of four Dirac cones inherited from each graphene layer. An applied bias voltage l...

[Phys. Rev. Lett. 120, 266402] Published Thu Jun 28, 2018

]]>We study a time-reversal-invariant topological superconductor island hosting spatially separated Majorana Kramers pairs, with weak tunnel couplings to two $s$-wave superconducting leads. When the topological superconductor island is in the Coulomb blockade regime, we predict that a Josephson current f...

[Phys. Rev. Lett. 120, 267002] Published Thu Jun 28, 2018

]]>Composites formed from charged particles and magnetic flux tubes, proposed by Wilczek, are one model for anyons—particles obeying fractional statistics. Here we propose a scheme for realizing charged flux tubes, in which a charged object with an intrinsic magnetic dipole moment is placed between two...

[Phys. Rev. Lett. 120, 267201] Published Thu Jun 28, 2018

]]>At ultrafast timescales, the initial and final states of a first-order metal-insulator transition often coexist forming clusters of the two phases. Here, we report an unexpected third long-lived intermediate state emerging at the photoinduced first-order metal-insulator transition of ${\mathrm{La}}_{0.325}{\mathrm{Pr}}_{0.3}{\mathrm{Ca}}_{\mathrm{0...}}$

[Phys. Rev. Lett. 120, 267202] Published Thu Jun 28, 2018

]]>Experiments on spin glasses can now make precise measurements of the exponent $z(T)$ governing the growth of glassy domains, while our computational capabilities allow us to make quantitative predictions for experimental scales. However, experimental and numerical values for $z(T)$ have differed. We use...

[Phys. Rev. Lett. 120, 267203] Published Thu Jun 28, 2018

]]>A new topological invariant—a movable but unremovable Dirac cone—is identified by considering symmorphic and non-symmorphic space groups of gapped elementary band representations.

[Phys. Rev. Lett. 120, 266401] Published Wed Jun 27, 2018

]]>Bulk FeSe is a special iron-based material in which superconductivity emerges inside a well-developed nematic phase. We present a microscopic model for this nematic superconducting state, which takes into account the mixing between $s$-wave and $d$-wave pairing channels and the changes in the orbital sp...

[Phys. Rev. Lett. 120, 267001] Published Tue Jun 26, 2018

]]>Strain-controlled coupling between dark and bright bound excitons may enable on-chip exciton-based memory and circuitry.

[Phys. Rev. Lett. 120, 267401] Published Tue Jun 26, 2018

]]>Inelastic neutron scattering measurements are performed on single crystals of the antiferromagnetic compound ${\mathrm{Mn}}_{5}{\mathrm{Si}}_{3}$ in order to investigate the relation between the spin dynamics and the magnetothermodynamics properties. It is shown that, among the two stable antiferromagnetic phases of this compoun...

[Phys. Rev. Lett. 120, 257205] Published Fri Jun 22, 2018

]]>The specific heat of the Kondo insulator ${\mathrm{YbB}}_{12}$ has been measured up to 60 T. The Sommerfeld coefficient $\gamma $ significantly increases at around 50 T, where the insulator metal transition occurs with a steep increase of the magnetization. $\gamma $ reaches $67\text{\hspace{0.17em}}\text{\hspace{0.17em}}\mathrm{mJ}/(\mathrm{mol}\text{\hspace{0.17em}}{\mathrm{K}}^{2})$ at high fields, which directly indicates...

[Phys. Rev. Lett. 120, 257206] Published Fri Jun 22, 2018

]]>In order to realize superconductivity in cuprates with the ${T}^{\prime}$-type structure, not only chemical substitution (Ce doping) but also postgrowth reduction annealing is necessary. In the case of thin films, however, well-designed reduction annealing alone without Ce doping can induce superconductivity in...

[Phys. Rev. Lett. 120, 257001] Published Thu Jun 21, 2018

]]>We observe and explain theoretically strain-induced spin-wave routing in the bilateral composite multilayer. By means of Brillouin light scattering and microwave spectroscopy, we study the spin-wave transport across three adjacent magnonic stripes, which are strain coupled to a piezoelectric layer. ...

[Phys. Rev. Lett. 120, 257203] Published Thu Jun 21, 2018

]]>Neural-network-based machine learning is emerging as a powerful tool for obtaining phase diagrams when traditional regression schemes using local equilibrium order parameters are not available, as in many-body localized (MBL) or topological phases. Nevertheless, instances of machine learning offerin...

[Phys. Rev. Lett. 120, 257204] Published Thu Jun 21, 2018

]]>We develop a general microscopic theory describing the phonon decoherence of quantum dots and indistinguishability of the emitted photons in photonic structures. The coherence is found to depend fundamentally on the dimensionality of the structure resulting in vastly different performance for quantu...

[Phys. Rev. Lett. 120, 257401] Published Thu Jun 21, 2018

]]>Dirac semimetals possess Fermi-arc surface states, which will be a set of discrete surface subbands in a nanowire due to the quantum confinement effect. Here, we report a tunable Fano effect induced by the interference between the discrete surface states and continuous bulk states of a Dirac semimet...

[Phys. Rev. Lett. 120, 257701] Published Thu Jun 21, 2018

]]>Probing the Fermi sea and wave vector of composite fermions address whether they are present, and spin-polarized, in a particular fractional Hall state that is of relevance to topological quantum computing.

[Phys. Rev. Lett. 120, 256601] Published Wed Jun 20, 2018

]]>We combined scanning tunneling microscopy and locally resolved magnetic stray field measurements on the ferromagnetic semimetal ${\mathrm{EuB}}_{6}$, which exhibits a complex ferromagnetic order and a colossal magnetoresistance effect. In a zero magnetic field, scanning tunneling spectroscopy visualizes the existen...

[Phys. Rev. Lett. 120, 257201] Published Tue Jun 19, 2018

]]>We present the discovery and refinement by neutron powder diffraction of a new magnetic phase in the ${\mathrm{Na}}_{1-x}{\mathrm{Ca}}_{x}{\mathrm{Mn}}_{7}{\mathrm{O}}_{12}$ quadruple perovskite phase diagram, which is the incommensurate analogue of the well-known pseudo-CE phase of the simple perovskite manganites. We demonstrate that incommensurate magne...

[Phys. Rev. Lett. 120, 257202] Published Tue Jun 19, 2018

]]>We investigate the interplay between charge order and superconductivity near an antiferromagnetic quantum critical point using sign-problem-free Quantum Monte Carlo simulations. We establish that, when the electronic dispersion is particle-hole symmetric, the system has an emergent SU(2) symmetry th...

[Phys. Rev. Lett. 120, 247002] Published Fri Jun 15, 2018

]]>We show that the ${Z}_{N}$ Berry phase (Berry phase quantized into $2\pi /N$) provides a useful tool to characterize symmetry protected topological phases with correlation that can be directly computed through numerics of a relatively small system size. The ${Z}_{N}$ Berry phase is defined in a $N-1$-dimensional paramet...

[Phys. Rev. Lett. 120, 247202] Published Fri Jun 15, 2018

]]>Using the transversal vibration resonance of a suspended carbon nanotube as a charge detector for its embedded quantum dot, we investigate the case of strong Kondo correlations between a quantum dot and its leads. We demonstrate that even when large Kondo conductance is carried at odd electron numbe...

[Phys. Rev. Lett. 120, 246802] Published Thu Jun 14, 2018

]]>A significantly enhanced Meissner effect is found in copper-coated niobium film as well as in copper-niobium-cobalt heterostructures.

[Phys. Rev. Lett. 120, 247001] Published Thu Jun 14, 2018

]]>We study a continuum of photonic quasicrystal heterostructures derived from local isomorphism (LI) classes of pentagonal quasicrystal tilings. These tilings are obtained by direct projection from a five-dimensional hypercubic lattice. We demonstrate that, with the sole exception of the Penrose LI cl...

[Phys. Rev. Lett. 120, 247401] Published Thu Jun 14, 2018

]]>By applying measurements of the dielectric constants and relative length changes to the dimerized molecular conductor $\kappa \text{\u2212}(\mathrm{BEDT}\text{\u2212}\mathrm{TTF}{)}_{2}\mathrm{Hg}(\mathrm{SCN}{)}_{2}\mathrm{Cl}$, we provide evidence for order-disorder type electronic ferroelectricity that is driven by the charge order within the $(\mathrm{BEDT}\text{\u2212}\mathrm{TTF}{)}_{2}$ dimers and stabilized by a ...

[Phys. Rev. Lett. 120, 247601] Published Thu Jun 14, 2018

]]>We analyze the measured optical conductivity spectra using the density-functional-theory-based electronic structure calculation and density-matrix renormalization group calculation of an effective model. We show that, in contrast to a conventional description, the Bose-Einstein condensation of prefo...

[Phys. Rev. Lett. 120, 247602] Published Thu Jun 14, 2018

]]>A new effective Hamiltonian for the disordered one-dimensional Hubbard model answers the question why charges, but not spins, are localized in this model.

[Phys. Rev. Lett. 120, 246602] Published Wed Jun 13, 2018

]]>Time-domain techniques have shown the potential of photomanipulating existing orders and inducing new states of matter in strongly correlated materials. Using time-resolved exact diagonalization, we perform numerical studies of pump dynamics in a Mott-Peierls system with competing charge and spin de...

[Phys. Rev. Lett. 120, 246402] Published Tue Jun 12, 2018

]]>The valley can serve as a new degree of freedom in the manipulation of particles or waves in condensed matter physics, whereas systems containing combinations of gain and loss elements constitute rich building units that can mimic non-Hermitian properties. By introducing gain and loss in artificial ...

[Phys. Rev. Lett. 120, 246601] Published Tue Jun 12, 2018

]]>Combining concepts of semiconductor physics and corrosion science, we develop a novel approach that allows us to perform *ab initio* calculations under controlled potentiostat conditions for electrochemical systems. The proposed approach can be straightforwardly applied in standard density functional ...

[Phys. Rev. Lett. 120, 246801] Published Tue Jun 12, 2018

]]>We study the excitation spectrum in the dimer phase of the Shastry-Sutherland model by using an unbiased variational method that works in the thermodynamic limit. The method outputs dynamical correlation functions in all possible channels. This output is exploited to identify the order parameters wi...

[Phys. Rev. Lett. 120, 247201] Published Tue Jun 12, 2018

]]>Understanding spin excitations and their connection to unconventional superconductivity have remained central issues since the discovery of cuprates. Direct measurement of the dynamical spin structure factor in the parent compounds can provide key information on important interactions relevant in th...

[Phys. Rev. Lett. 120, 246401] Published Mon Jun 11, 2018

]]>In two dimensions, dephasing by a bath cuts off Anderson localization that would otherwise occur at any energy density for fermions with disorder. For an isolated system with short-range interactions, the system can be its own bath, exhibiting diffusive (non-Markovian) thermal density fluctuations. ...

[Phys. Rev. Lett. 120, 236601] Published Fri Jun 08, 2018

]]>We investigate wetting phenomena near graphene within the Dzyaloshinskii-Lifshitz-Pitaevskii theory for light gases of hydrogen, helium, and nitrogen in three different geometries where graphene is either affixed to an insulating substrate, submerged or suspended. We find that the presence of graphe...

[Phys. Rev. Lett. 120, 236802] Published Fri Jun 08, 2018

]]>${\mathrm{SrTiO}}_{3}$ exhibits a superconducting dome upon doping with Nb, with a maximum critical temperature ${T}_{c}\approx 0.4\text{\hspace{0.17em}}\text{\hspace{0.17em}}\mathrm{K}$. Using microwave stripline resonators at frequencies from 2 to 23 GHz and temperatures down to 0.02 K, we probe the low-energy optical response of superconducting ${\mathrm{SrTiO}}_{3}$ with a charge carrier co...

[Phys. Rev. Lett. 120, 237002] Published Fri Jun 08, 2018

]]>Temperature-pressure phase diagram of the Kitaev hyperhoneycomb iridate $\beta \text{\u2212}{\mathrm{Li}}_{2}{\mathrm{IrO}}_{3}$ is explored using magnetization, thermal expansion, magnetostriction, and muon spin rotation measurements, as well as single-crystal x-ray diffraction under pressure and *ab initio* calculations. The Néel temperature of $\mathrm{...}$

[Phys. Rev. Lett. 120, 237202] Published Fri Jun 08, 2018

]]>We study the dynamics of a Skyrmion in a magnetic insulating nanowire in the presence of time-dependent oscillating magnetic field gradients. These ac fields act as a net driving force on the Skyrmion via its own intrinsic magnetic excitations. In a microscopic quantum field theory approach, we incl...

[Phys. Rev. Lett. 120, 237203] Published Fri Jun 08, 2018

]]>We report electron spin resonance (ESR) spectroscopy results on the double perovskite ${\mathrm{Ba}}_{2}{\mathrm{YIrO}}_{6}$. On general grounds, this material is expected to be nonmagnetic due to the strong coupling of the spin and orbital momenta of ${\mathrm{Ir}}^{5+}$ ($5{d}^{4}$) ions. However, controversial experimental reports on either strong ...

[Phys. Rev. Lett. 120, 237204] Published Fri Jun 08, 2018

]]>Black phosphorus (BP), an elemental semiconductor, has attracted tremendous interest because it exhibits a wealth of interesting electronic and optoelectronic properties in equilibrium condition. The nonequilibrium electronic structures of bulk BP under a periodic field of laser remain unexplored, b...

[Phys. Rev. Lett. 120, 237403] Published Fri Jun 08, 2018

]]>Scalable architectures for quantum information technologies require one to selectively couple long-distance qubits while suppressing environmental noise and cross talk. In semiconductor materials, the coherent coupling of a single spin on a quantum dot to a cavity hosting fermionic modes offers a ne...

[Phys. Rev. Lett. 120, 236801] Published Thu Jun 07, 2018

]]>A superdirective cylindrical nanoantenna is demonstrated with a multilayered cylindrical metamaterial-inspired structure. Targeting specific scattering coefficients for the dipole and higher-order modes, the ideal limit of needle radiation is demonstrated. A five-layer system is optimized to demonst...

[Phys. Rev. Lett. 120, 237401] Published Wed Jun 06, 2018

]]>The famous vanishing of the density of states (DOS) in a band gap, be it photonic or electronic, pertains to the infinite-crystal limit. In contrast, all experiments and device applications refer to finite crystals, which raises the question: Upon increasing the linear size $L$ of a crystal, how fast ...

[Phys. Rev. Lett. 120, 237402] Published Wed Jun 06, 2018

]]>The recent observation of replica bands in single-layer $\mathrm{FeSe}/{\mathrm{SrTiO}}_{3}$ by angle-resolved photoemission spectroscopy (ARPES) has triggered intense discussions concerning the potential influence of the FeSe electrons coupling with substrate phonons on the superconducting transition temperature. Here we p...

[Phys. Rev. Lett. 120, 237001] Published Tue Jun 05, 2018

]]>The excitation of an antiferromagnetic resonance in metallic Mn${}_{2}$Au with THz pulses exceeds excitations found in antiferromagnetic insulators by three orders of magnitude.

[Phys. Rev. Lett. 120, 237201] Published Tue Jun 05, 2018

]]>We consider charge pumping in a system of parafermions, implemented at fractional quantum Hall edges. Our pumping protocol leads to a noisy behavior of the pumped current. As the adiabatic limit is approached, not only does the noisy behavior persist but the counting statistics of the pumped current...

[Phys. Rev. Lett. 120, 226802] Published Fri Jun 01, 2018

]]>The dispersion law for plasma oscillations in a two-dimensional electron gas in the hydrodynamic approximation interpolates between $\mathrm{\Omega}\propto \sqrt{q}$ and $\mathrm{\Omega}\propto q$ dependences as the wave vector $q$ increases. As a result, downstream of a charged impurity in the presence of a uniform supersonic electric current flow, a w...

[Phys. Rev. Lett. 120, 226801] Published Thu May 31, 2018

]]>Magnetic skyrmions in noncentrosymmetric helimagnets with ${D}_{n}$ symmetry are Bloch-type magnetization swirls with a helicity angle of $\pm 90\xb0$. At the surface of helimagnetic thin films below a critical thickness, a twisted skyrmion state with an arbitrary helicity angle has been proposed; however, its dir...

[Phys. Rev. Lett. 120, 227202] Published Thu May 31, 2018

]]>We report on high-dimensional quantum dynamical simulations of photoinduced exciton migration in a single-chain oligothiophene segment, in view of elucidating the controversial nature of the elementary exciton transport steps in semiconducting polymers. A novel first-principles parametrized Frenkel $\mathrm{...}$

[Phys. Rev. Lett. 120, 227401] Published Thu May 31, 2018

]]>Two-dimensional out-of-plane ferroelectric ordering is experimentally demonstrated in an atomically thin crystal.

[Phys. Rev. Lett. 120, 227601] Published Thu May 31, 2018

]]>The temperature dependence of the excitation spectrum in ${\mathrm{NaOsO}}_{3}$ through its metal-to-insulator transition (MIT) at 410 K has been investigated using resonant inelastic x-ray scattering at the Os ${L}_{3}$ edge. High-resolution ($\mathrm{\Delta}E\sim 56\text{\hspace{0.17em}}\text{\hspace{0.17em}}\mathrm{meV}$) measurements show that the well-defined, low-energy magnons in the ...

[Phys. Rev. Lett. 120, 227203] Published Wed May 30, 2018

]]>Magnetic domain walls are objects whose dynamics is inseparably connected to their structure. In this Letter, we investigate magnetic bilayers, which are engineered such that a coupled pair of domain walls, one in each layer, is stabilized by a cooperation of Dzyaloshinskii-Moriya interaction and fl...

[Phys. Rev. Lett. 120, 227204] Published Wed May 30, 2018

]]>We demonstrate an acoustical analog of a circuit quantum electrodynamics system that leverages acoustic properties to enable strong multimode coupling in the dispersive regime while suppressing spontaneous emission to unconfined modes. Specifically, we fabricate and characterize a device that compri...

[Phys. Rev. Lett. 120, 227701] Published Wed May 30, 2018

]]>We realize a superconducting circuit analog of the generic cavity-optomechanical Hamiltonian by longitudinally coupling two superconducting resonators, which are an order of magnitude different in frequency. We achieve longitudinal coupling by embedding a superconducting quantum interference device ...

[Phys. Rev. Lett. 120, 227702] Published Wed May 30, 2018

]]>We present measurements on a series of materials, ${\mathrm{Li}}_{2}{\mathrm{In}}_{1-x}{\mathrm{Sc}}_{x}{\mathrm{Mo}}_{3}{\mathrm{O}}_{8}$, that can be described as a $1/6$th-filled breathing kagome lattice. Substituting Sc for In generates chemical pressure which alters the breathing parameter nonmonotonically. Muon spin rotation experiments show that this chemical press...

[Phys. Rev. Lett. 120, 227201] Published Tue May 29, 2018

]]>Electron correlation effects are studied in ZrSiS using a combination of first-principles and model approaches. We show that basic electronic properties of ZrSiS can be described within a two-dimensional lattice model of two nested square lattices. A high degree of electron-hole symmetry characteris...

[Phys. Rev. Lett. 120, 216401] Published Fri May 25, 2018

]]>The topological phases of periodically driven, or Floquet systems, rely on a perfectly periodic modulation of system parameters in time. Even the smallest deviation from periodicity leads to decoherence, causing the boundary (end) states to leak into the system’s bulk. Here, we show that in one dime...

[Phys. Rev. Lett. 120, 216801] Published Fri May 25, 2018

]]>The emergence of a magnetic field when the material is bent is predicted to be a signature for chiral superconductivity.

[Phys. Rev. Lett. 120, 217002] Published Fri May 25, 2018

]]>The Kitaev quantum spin liquid displays the fractionalization of quantum spins into Majorana fermions. The emergent Majorana edge current is predicted to manifest itself in the form of a finite thermal Hall effect, a feature commonly discussed in topological superconductors. Here we report on therma...

[Phys. Rev. Lett. 120, 217205] Published Fri May 25, 2018

]]>The singularities of the dynamical response function are one of the most remarkable effects in many-body interacting systems. However in one dimension these divergences only exist strictly at zero temperature, making their observation very difficult in most cold atomic experimental settings. Moreove...

[Phys. Rev. Lett. 120, 217206] Published Fri May 25, 2018

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