The standard quantum limit constrains the precision of an oscillator position measurement. It arises from a balance between the imprecision and the quantum backaction of the measurement. However, a measurement of only a single quadrature of the oscillator can evade the backaction and be made with ar…

[Phys. Rev. Lett. 117, 140401] Published Mon Sep 26, 2016

]]>In recent measurements of the scissors mode in radiative decay experiments, transition strengths were observed that were double that expected from theory and systematics well established from measurements on the radiative excitation channel, that is, using nuclear resonance fluorescence (NRF). Addit…

[Phys. Rev. Lett. 117, 142501] Published Mon Sep 26, 2016

]]>A new approach to calculating the properties of molecules and solids may offer higher accuracy at reasonable computational cost, accelerating the discovery of useful materials.

[Phys. Rev. Lett. 117, 143002] Published Mon Sep 26, 2016

]]>We perform extensive molecular dynamics simulations of a charged polymer in a good solvent in the regime where the chain is collapsed. We analyze the dependence of the gyration radius ${R}_{g}$ on the reduced Bjerrum length ${\ell}_{B}$ and find two different regimes. In the first one, called a weak electrostatic re…

[Phys. Rev. Lett. 117, 147801] Published Mon Sep 26, 2016

]]>We have detected visible photons emitted from the thermally populated electronic excited state, namely recurrent fluorescence (RF), of ${\mathrm{C}}_{6}^{-}$ stored in an electrostatic ion storage ring. Clear evidence is provided to distinguish RF from normal fluorescence, based on the temporal profile of detected pho…

[Phys. Rev. Lett. 117, 133004] Published Fri Sep 23, 2016

]]>Up to 75% of light reflects from just 2000 atoms aligned along an optical fiber, an arrangement that could be useful in photonic circuits.

[Phys. Rev. Lett. 117, 133603] Published Fri Sep 23, 2016

]]>Up to 75% of light reflects from just 2000 atoms aligned along an optical fiber, an arrangement that could be useful in photonic circuits.

[Phys. Rev. Lett. 117, 133604] Published Fri Sep 23, 2016

]]>We consider the consequence of nonreciprocity in near-field heat transfer by studying systems consisting of magneto-optical nanoparticles. We demonstrate that, in thermal equilibrium, a nonreciprocal many-body system in heat transfer can support a persistent directional heat current, without violati…

[Phys. Rev. Lett. 117, 134303] Published Fri Sep 23, 2016

]]>The unique properties of the individual lipids that compose biological membranes together determine the energetics of the surface. The energetics of the surface, in turn, govern the formation of membrane structures and membrane reshaping processes, and thus they will underlie cellular-scale models o…

[Phys. Rev. Lett. 117, 138104] Published Fri Sep 23, 2016

]]>We consider the nonequilibrium time evolution of a translationally invariant state under a Hamiltonian with a localized defect. We discern the situations where a light cone spreads out from the defect and separates the system into regions with macroscopically different properties. We identify the li…

[Phys. Rev. Lett. 117, 130402] Published Thu Sep 22, 2016

]]>The double polarization observable $E$ and the helicity dependent cross sections ${\sigma}_{1/2}$ and ${\sigma}_{3/2}$ were measured for $\eta $ photoproduction from quasifree protons and neutrons. The circularly polarized tagged photon beam of the A2 experiment at the Mainz MAMI accelerator was used in combination with a longitud…

[Phys. Rev. Lett. 117, 132502] Published Thu Sep 22, 2016

]]>Coherent optical control of individual particles has been demonstrated both for atoms and semiconductor quantum dots. Here we demonstrate the emergence of quantum coherent effects in semiconductor Rydberg excitons in bulk ${\mathrm{Cu}}_{2}\mathrm{O}$. Because of the spectral proximity between two adjacent Rydberg exciton s…

[Phys. Rev. Lett. 117, 133003] Published Thu Sep 22, 2016

]]>We present a general theory of bicircular high-order-harmonic generation from $N$-fold rotationally symmetric molecules. Using a rotating frame of reference we predict the complete structure of the high-order-harmonic spectra for arbitrary driving frequency ratios and show how molecular symmetries can…

[Phys. Rev. Lett. 117, 133902] Published Thu Sep 22, 2016

]]>Controlling waves in complex media has become a major topic of interest, notably through the concepts of time reversal and wave front shaping. Recently, it was shown that spatial light modulators can counterintuitively focus waves both in space and time through multiple scattering media when illumin…

[Phys. Rev. Lett. 117, 134302] Published Thu Sep 22, 2016

]]>We introduce a particle-hole-symmetric metallic state of bosons in a magnetic field at odd-integer filling. This state hosts composite fermions whose energy dispersion features a quadratic band touching and corresponding $2\pi $ Berry flux protected by particle-hole and discrete rotation symmetries. We a…

[Phys. Rev. Lett. 117, 136802] Published Thu Sep 22, 2016

]]>We have studied electron states present at the Pb(111) surface above Ar-filled nanocavities created by ion beam irradiation and annealing. Vertical confinement between the parallel crystal and nanocavity surfaces creates a series of quantum well state subbands. Differential conductance data measured…

[Phys. Rev. Lett. 117, 136803] Published Thu Sep 22, 2016

]]>We present a theoretical and experimental study of the interplay between spin-orbit coupling (SOC), Coulomb interaction, and motion of conduction electrons in a magnetized two-dimensional electron gas. Via a transformation of the many-body Hamiltonian we introduce the concept of spin-orbit twisted s…

[Phys. Rev. Lett. 117, 137204] Published Thu Sep 22, 2016

]]>Coherent x-ray diffraction imaging via an iterative phase retrieval approach allows for the visualization of the 3D positions of individual particles in a single colloidal crystal grain.

[Phys. Rev. Lett. 117, 138002] Published Thu Sep 22, 2016

]]>A new model shows that tissue growth is crucial for explaining the formation of hierarchical and optimized vascular networks, such as those seen in plants and animals.

[Phys. Rev. Lett. 117, 138301] Published Thu Sep 22, 2016

]]>[Phys. Rev. Lett. 117, 139701] Published Thu Sep 22, 2016

]]>[Phys. Rev. Lett. 117, 139702] Published Thu Sep 22, 2016

]]>[Phys. Rev. Lett. 117, 139801] Published Thu Sep 22, 2016

]]>[Phys. Rev. Lett. 117, 139802] Published Thu Sep 22, 2016

]]>Nonlocality is a fundamental trait of quantum many-body systems, both at the level of pure states, as well as at the level of mixed states. Because of nonlocality, mixed states of any two subsystems are correlated in a stronger way than what can be accounted for by considering the correlated probabi…

[Phys. Rev. Lett. 117, 130401] Published Wed Sep 21, 2016

]]>Motivated by limitations and capabilities of neutral atom qubits, we examine whether measurement-free error correction can produce practical error thresholds. We show that this can be achieved by extracting redundant syndrome information, giving our procedure extra fault tolerance and eliminating th…

[Phys. Rev. Lett. 117, 130503] Published Wed Sep 21, 2016

]]>We point out a surprising consequence of the usually assumed initial conditions for cosmological perturbations. Namely, a spectrum of Gaussian, linear, adiabatic, scalar, growing mode perturbations not only creates acoustic oscillations of the kind observed on very large scales today, it also leads …

[Phys. Rev. Lett. 117, 131301] Published Wed Sep 21, 2016

]]>A new study of the cosmic microwave background places the strictest limits to date on a rotating Universe and other forms of cosmic anisotropy.

[Phys. Rev. Lett. 117, 131302] Published Wed Sep 21, 2016

]]>We address a long-standing problem of describing the thermodynamics of an accelerating black hole. We derive a standard first law of black hole thermodynamics, with the usual identification of entropy proportional to the area of the event horizon—even though the event horizon contains a conical sing…

[Phys. Rev. Lett. 117, 131303] Published Wed Sep 21, 2016

]]>We use the conformal bootstrap program to derive the necessary conditions for emergent symmetry enhancement from discrete symmetry (e.g., ${\mathbb{Z}}_{n}$) to continuous symmetry [e.g., $U(1)$] under the renormalization group flow. In three dimensions, in order for ${\mathbb{Z}}_{2}$ symmetry to be enhanced to $U(1)$ symmetry, the c…

[Phys. Rev. Lett. 117, 131601] Published Wed Sep 21, 2016

]]>We study the entanglement structure of lattice gauge theories from the local operational point of view, and, similar to Soni and Trivedi [J. High Energy Phys. 1 (**2016**) 1], we show that the usual entanglement entropy for a spatial bipartition can be written as the sum of an undistillable gauge part a…

[Phys. Rev. Lett. 117, 131602] Published Wed Sep 21, 2016

]]>We present a new paradigm for the design of exchange-correlation functionals in density-functional theory. Electron pairs are correlated explicitly by means of the recently developed second order Bethe-Goldstone equation (BGE2) approach. Here we propose a screened BGE2 (sBGE2) variant that efficient…

[Phys. Rev. Lett. 117, 133002] Published Wed Sep 21, 2016

]]>An enhancement in Brillouin light scattering of optical photons with magnons is demonstrated in magneto-optical whispering gallery mode resonators tuned to a triple-resonance point. This occurs when both the input and output optical modes are resonant with those of the whispering gallery resonator, …

[Phys. Rev. Lett. 117, 133602] Published Wed Sep 21, 2016

]]>A stable nanoscale thermal hot spot, with temperature approaching $100\text{\hspace{0.17em}}\xb0\mathrm{C}$, is shown to be sustained by localized Ohmic heating of a focused electric field at the tip of a slender conic nanopore. The self-similar (length-independent) conic geometry allows us to match the singular heat source at the ti…

[Phys. Rev. Lett. 117, 134301] Published Wed Sep 21, 2016

]]>New evidence indicates that there is significant 3D variation in density fluctuations near the boundary of weakly 3D tokamak plasmas when resonant magnetic perturbations are applied to suppress transient edge instabilities. The increase in fluctuations is concomitant with an increase in the measured…

[Phys. Rev. Lett. 117, 135001] Published Wed Sep 21, 2016

]]>Despite the fact that phase-change materials are widely used for data storage, no consensus exists on the unique mechanism of their ultrafast phase change and its accompanied large and rapid optical change. By using the pump-probe observation method combining a femtosecond optical laser and an x-ray…

[Phys. Rev. Lett. 117, 135501] Published Wed Sep 21, 2016

]]>From first-principles molecular dynamics, we investigate the relation between the superionic proton conduction and the behavior of the $\mathrm{O}\u2500\mathrm{H}\cdots \mathrm{O}$ bond (ice ${\mathrm{VII}}^{\prime}$ to ice X transition) in body-centered-cubic (bcc) ${\mathrm{H}}_{2}\mathrm{O}$ ice between 1300 and 2000 K and up to 300 GPa. We bring evidence that there are three dist…

[Phys. Rev. Lett. 117, 135503] Published Wed Sep 21, 2016

]]>The pressure effects on plastic deformation and phase transformation mechanisms of materials are of great importance to both Earth science and technological applications. Zircon-type materials are abundant in both nature and the industrial field; however, there is still no *in situ* study of their def…

[Phys. Rev. Lett. 117, 135701] Published Wed Sep 21, 2016

]]>The avoidance of water freezing is the holy grail in the cryopreservation of biological samples, food, and organs. Fast cooling rates are used to beat ice nucleation and avoid cell damage. This strategy can be enhanced by applying high pressures to decrease the nucleation rate, but the physics behin…

[Phys. Rev. Lett. 117, 135702] Published Wed Sep 21, 2016

]]>Optical reflectivity experiments on Cd${}_{3}$As${}_{2}$ indicate the presence of Kane electrons rather than Dirac fermions in this material. The results contradict those from recent ARPES experiments, but agree with recent STM results.

[Phys. Rev. Lett. 117, 136401] Published Wed Sep 21, 2016

]]>We demonstrate that topological Dirac semimetals, which possess two Dirac nodes, separated in momentum space along a rotation axis and protected by rotational symmetry, exhibit an additional quantum anomaly, distinct from the chiral anomaly. This anomaly, which we call the ${\mathbb{Z}}_{2}$ anomaly, is a consequen…

[Phys. Rev. Lett. 117, 136602] Published Wed Sep 21, 2016

]]>We study the glass formation in two- and three-dimensional Ising and Heisenberg spin systems subject to competing interactions and uniaxial anisotropy with a mean-field approach. In three dimensions, for sufficiently strong anisotropy the systems always modulate in a striped phase. Below a critical …

[Phys. Rev. Lett. 117, 137201] Published Wed Sep 21, 2016

]]>We construct an exact map between a tight-binding model on any bipartite lattice in the presence of dephasing noise and a Hubbard model with imaginary interaction strength. In one dimension, the exact many-body Liouvillian spectrum can be obtained by application of the Bethe ansatz method. We find t…

[Phys. Rev. Lett. 117, 137202] Published Wed Sep 21, 2016

]]>We present the first materials specific *ab initio* theory of the magnetization induced by circularly polarized laser light in metals. Our calculations are based on nonlinear density matrix theory and include the effect of absorption. We show that the induced magnetization, commonly referred to as inv…

[Phys. Rev. Lett. 117, 137203] Published Wed Sep 21, 2016

]]>A swelling brain bulging out of a circular opening in the skull exhibits a stress singularity (similar to that seen for punch indentation) at the point of contact with the skull.

[Phys. Rev. Lett. 117, 138001] Published Wed Sep 21, 2016

]]>We present a theoretical analysis that associates the resonances of extraordinary acoustic Raman (EAR) spectroscopy [Wheaton *et al.*, Nat. Photonics **9**, 68 (2015)] with the collective modes of proteins. The theory uses the anisotropic elastic network model to find the protein acoustic modes, and calcu…

[Phys. Rev. Lett. 117, 138101] Published Wed Sep 21, 2016

]]>Membrane tubes and tubular networks are ubiquitous in living cells. Inclusions like proteins are vital for both the stability and the dynamics of such networks. These inclusions interact via the curvature deformations they impose on the membrane. We analytically study the resulting membrane mediated…

[Phys. Rev. Lett. 117, 138102] Published Wed Sep 21, 2016

]]>In recent experiments [T. Basta *et al.*, Proc. Natl. Acad. Sci. U.S.A. **111**, 670 (2014)] lipids and membrane proteins were observed to self-assemble into membrane protein polyhedral nanoparticles (MPPNs) with a well-defined polyhedral protein arrangement and characteristic size. We develop a model of…

[Phys. Rev. Lett. 117, 138103] Published Wed Sep 21, 2016

]]>A Bose-Einstein condensate is used as an atomic source for a high precision sensor. A $5\times 1{0}^{6}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\mathrm{atom}$ $F=1$ spinor condensate of ${}^{87}\mathrm{Rb}$ is released into free fall for up to 750 ms and probed with a $T=130\text{\hspace{0.17em}}\text{\hspace{0.17em}}\mathrm{ms}$ Mach-Zehnder atom interferometer based on Bragg transitions. The Bragg interferometer simultaneously…

[Phys. Rev. Lett. 117, 138501] Published Wed Sep 21, 2016

]]>The emerging field of quantum machine learning has the potential to substantially aid in the problems and scope of artificial intelligence. This is only enhanced by recent successes in the field of classical machine learning. In this work we propose an approach for the systematic treatment of machin…

[Phys. Rev. Lett. 117, 130501] Published Tue Sep 20, 2016

]]>Selective control of qubits in a quantum register for the purposes of quantum information processing represents a critical challenge for dense spin ensembles in solid-state systems. Here we present a protocol that achieves a complete set of selective electron-nuclear gates and single nuclear rotatio…

[Phys. Rev. Lett. 117, 130502] Published Tue Sep 20, 2016

]]>Using synchrotron radiation and high-resolution electron spectroscopy, we have directly observed and identified specific photoelectrons from ${K}^{-2}V$ states in neon corresponding to simultaneous $1s$ ionization and $1s\to \text{valence}$ excitation. The natural lifetime broadening of the ${K}^{-2}V$ states and the relative …

[Phys. Rev. Lett. 117, 133001] Published Tue Sep 20, 2016

]]>Atoms undergoing strong-field ionization in two-color circularly polarized femtosecond laser fields exhibit unique two-dimensional photoelectron trajectories and can emit bright circularly polarized extreme ultraviolet and soft-x-ray beams. In this Letter, we present the first experimental observati…

[Phys. Rev. Lett. 117, 133201] Published Tue Sep 20, 2016

]]>We report on nonsequential double ionization of Ar by a laser pulse consisting of two counterrotating circularly polarized fields (390 and 780 nm). The double-ionization probability depends strongly on the relative intensity of the two fields and shows a kneelike structure as a function of intensity…

[Phys. Rev. Lett. 117, 133202] Published Tue Sep 20, 2016

]]>Powerful incoherent laser pulses can propagate in focusing Kerr media much longer distances than can coherent pulses, due to the fast phase mixing that prevents transverse filamentation. This distance is limited by 4-wave scattering, which accumulates waves at small transverse wave numbers, where ph…

[Phys. Rev. Lett. 117, 133901] Published Tue Sep 20, 2016

]]>The macroscopic behavior of dense suspensions of neutrally buoyant spheres in turbulent plane channel flow is examined. We show that particles larger than the smallest turbulence scales cause the suspension to deviate from the continuum limit in which its dynamics is well described by an effective s…

[Phys. Rev. Lett. 117, 134501] Published Tue Sep 20, 2016

]]>The crossover between a metal and a Mott insulator leads to a localization of fermions from delocalized Bloch states to localized states. We experimentally study this crossover using fermionic atoms in an optical lattice by measuring thermodynamic and local (on-site) density correlations. In the met…

[Phys. Rev. Lett. 117, 135301] Published Tue Sep 20, 2016

]]>We show that an interplay between quantum effects, strong on-site ferromagnetic exchange interaction, and antiferromagnetic correlations in Kondo lattices can give rise to an exotic spin-orbit coupled metallic state in regimes where classical treatments predict a trivial insulating behavior. This ph…

[Phys. Rev. Lett. 117, 135302] Published Tue Sep 20, 2016

]]>Elpasolite is the predominant quaternary crystal structure (${\mathrm{AlNaK}}_{2}{\mathrm{F}}_{6}$ prototype) reported in the Inorganic Crystal Structure Database. We develop a machine learning model to calculate density functional theory quality formation energies of all $\sim 2\times {10}^{6}$ pristine $AB{C}_{2}{D}_{6}$ elpasolite crystals that can be ma…

[Phys. Rev. Lett. 117, 135502] Published Tue Sep 20, 2016

]]>Gapless spin liquids have recently been observed in several frustrated Mott insulators, with elementary spin excitations—“spinons”—reminiscent of degenerate Fermi systems. However, their precise role at the Mott point, where charge fluctuations begin to proliferate, remains controversial and ill und…

[Phys. Rev. Lett. 117, 136601] Published Tue Sep 20, 2016

]]>The energy and momentum selectivity of time- and angle-resolved photoemission spectroscopy is exploited to address the ultrafast dynamics of the antiferromagnetic spin density wave (SDW) transition photoexcited in epitaxial thin films of chromium. We are able to quantitatively extract the evolution …

[Phys. Rev. Lett. 117, 136801] Published Tue Sep 20, 2016

]]>The rich variety of iron-based superconductors and their complex electronic structure lead to a wide range of possibilities for gap symmetry and pairing components. Here we solve in the two-Fe Brillouin zone the full frequency-dependent linearized Eliashberg equations to investigate spin-fluctuation…

[Phys. Rev. Lett. 117, 137001] Published Tue Sep 20, 2016

]]>[Phys. Rev. Lett. 117, 139901] Published Tue Sep 20, 2016

]]>Simulations predict that the ground states of certain light nuclei lie near a quantum phase transition between a liquid-like phase and a phase involving clusters of alpha particles.

[Phys. Rev. Lett. 117, 132501] Published Mon Sep 19, 2016

]]>The transverse component of a superconducting qubit is continuously measured for the first time, showing quantum jumps between its eigenstates.

[Phys. Rev. Lett. 117, 133601] Published Mon Sep 19, 2016

]]>The PandaX-II experiment reports results from their first full physics run in search of dark matter. They find none, and their data cut in half the existing upper limit on the scattering cross section for 40 GeV WIMPS.

[Phys. Rev. Lett. 117, 121303] Published Fri Sep 16, 2016

]]>One of the fundamental questions of theoretical cosmology is whether the Universe can undergo a nonsingular bounce, i.e., smoothly transit from a period of contraction to a period of expansion through violation of the null energy condition (NEC) at energies well below the Planck scale and at finite …

[Phys. Rev. Lett. 117, 121304] Published Fri Sep 16, 2016

]]>Axions, if they make up the dark mater, could form dense stars balanced by gravity and the mean-field pressure of the axion Bose-Einstein condensate.

[Phys. Rev. Lett. 117, 121801] Published Fri Sep 16, 2016

]]>We have performed high resolution photoassociation spectroscopy of rubidium ultralong-range Rydberg molecules in the vicinity of the $25P$ state. Because of the hyperfine interaction in the ground state perturber atom, the emerging mixed singlet-triplet potentials contain contributions from both hyper…

[Phys. Rev. Lett. 117, 123002] Published Fri Sep 16, 2016

]]>Magnons in ferrimagnetic insulators such as yttrium iron garnet (YIG) have recently emerged as promising candidates for coherent information processing in microwave circuits. Here we demonstrate optical whispering gallery modes of a YIG sphere interrogated by a silicon nitride photonic waveguide, wi…

[Phys. Rev. Lett. 117, 123605] Published Fri Sep 16, 2016

]]>A new device that can potentially be scaled up for quantum computing converts visible light to infrared light suitable for fiber-optic transmission without destroying the light’s quantum state.

[Phys. Rev. Lett. 117, 123902] Published Fri Sep 16, 2016

]]>We study the possibility of producing x-gamma rays with orbital angular momentum by means of the inverse Compton backscattering between a high brightness electron beam and a twisted laser pulse. We use the classical electrodynamics retarded fields for evaluating the orbital angular momentum of the r…

[Phys. Rev. Lett. 117, 123903] Published Fri Sep 16, 2016

]]>Plasmons provide excellent sensitivity to detect analyte molecules through their strong interaction with the dielectric environment. Plasmonic sensors based on noble metals are, however, limited by the spectral broadening of these excitations. Here we identify a new mechanism that reveals the presen…

[Phys. Rev. Lett. 117, 123904] Published Fri Sep 16, 2016

]]>A geometrically frustrated elastic body will develop residual stresses arising from the mismatch between the intrinsic geometry of the body and the geometry of the ambient space. We analyze these stresses for an ambient space with gradients in its intrinsic curvature, and show that residual stresses…

[Phys. Rev. Lett. 117, 124101] Published Fri Sep 16, 2016

]]>Using a new two-stage acceleration scheme, where electron injection and seeding are controlled in different periods of the laser wakefield, high-quality tunable electron beams are produced with brightnesses close to those achieved in state-of-the-art linac drivers.

[Phys. Rev. Lett. 117, 124801] Published Fri Sep 16, 2016

]]>We consider the efficiency limit of relativistic high-order-harmonic emission from solid targets achievable with tailored light fields. Using one-dimensional particle-in-cell simulations, the maximum energy conversion efficiency is shown to reach as high as 10% for the harmonics in the range of 80–2…

[Phys. Rev. Lett. 117, 125001] Published Fri Sep 16, 2016

]]>A new, frequency modulation mechanism for zonal flow pattern formation is presented. The model predicts the probability distribution function of the flow strength as well as the evolution of the characteristic spatial scale. Magnetic toroidicity-induced global phase dynamics is shown to determine th…

[Phys. Rev. Lett. 117, 125002] Published Fri Sep 16, 2016

]]>We study the zero-temperature phase diagram of a spin-orbit-coupled Bose-Einstein condensate of spin 1, with equally weighted Rashba and Dresselhaus couplings. Depending on the antiferromagnetic or ferromagnetic nature of the interactions, we find three kinds of striped phases with qualitatively dif…

[Phys. Rev. Lett. 117, 125301] Published Fri Sep 16, 2016

]]>Novel ground states might be realized in honeycomb lattices with strong spin-orbit coupling. Here we study the electronic structure of $\alpha \text{\u2212}{\mathrm{RuCl}}_{3}$, in which the Ru ions are in a ${d}^{5}$ configuration and form a honeycomb lattice, by angle-resolved photoemission, x-ray photoemission, and electron energy loss …

[Phys. Rev. Lett. 117, 126403] Published Fri Sep 16, 2016

]]>We consider a two-dimensional system initialized in a topologically trivial state before its Hamiltonian is ramped through a phase transition into a Chern insulator regime. This scenario is motivated by current experiments with ultracold atomic gases aimed at realizing time-dependent dynamics in top…

[Phys. Rev. Lett. 117, 126803] Published Fri Sep 16, 2016

]]>We have investigated charge transport in single-molecule junctions using gold nanoelectrodes at room and cryogenic (10 K) temperatures. A statistical analysis of the low-bias conductance, measured during the stretching of the molecular junctions, shows that the most probable single-molecule conducta…

[Phys. Rev. Lett. 117, 126804] Published Fri Sep 16, 2016

]]>The in-plane resistivity anisotropy is studied in strain-detwinned single crystals of FeSe. In contrast to other iron-based superconductors, FeSe does not develop long-range magnetic order below the tetragonal-to-orthorhombic transition at ${T}_{s}\approx 90\text{\hspace{0.17em}}\text{\hspace{0.17em}}\mathrm{K}$. This allows for the disentanglement of the contrib…

[Phys. Rev. Lett. 117, 127001] Published Fri Sep 16, 2016

]]>We calculate the resonant inelastic x-ray scattering (RIXS) response of the Kitaev honeycomb model, an exactly solvable quantum-spin-liquid model with fractionalized Majorana and flux excitations. We find that the fundamental RIXS channels, the spin-conserving (SC) and the non-spin-conserving (NSC) …

[Phys. Rev. Lett. 117, 127203] Published Fri Sep 16, 2016

]]>By combining angle-resolved photoemission spectroscopy and quantum oscillation measurements, we performed a comprehensive investigation on the electronic structure of LaSb, which exhibits near-quadratic extremely large magnetoresistance (XMR) without any sign of saturation at magnetic fields as high…

[Phys. Rev. Lett. 117, 127204] Published Fri Sep 16, 2016

]]>We show that, by monitoring the free carrier reservoir in a GaAs-based quantum well microcavity under nonresonant pulsed optical pumping, lasing supported by a fermionic reservoir (photon lasing) can be distinguished from lasing supported by a reservoir of bosons (polariton lasing). Carrier densitie…

[Phys. Rev. Lett. 117, 127401] Published Fri Sep 16, 2016

]]>We demonstrate through Brownian dynamics simulations a phase transition in plastic crystalline assemblies of Janus spheres through controlled pressure anisotropy. When the pressure in plane with hexagonally ordered layers is increased relative to that normal to the layers, a rapid first-order rotato…

[Phys. Rev. Lett. 117, 128001] Published Fri Sep 16, 2016

]]>Delay-coupled electro-optical systems have received much attention for their dynamical properties and their potential use in signal processing. In particular, it has recently been demonstrated, using the artificial intelligence algorithm known as reservoir computing, that photonic implementations of…

[Phys. Rev. Lett. 117, 128301] Published Fri Sep 16, 2016

]]>[Phys. Rev. Lett. 117, 129902] Published Fri Sep 16, 2016

]]>The $\rho (770)$ meson is the most extensively studied resonance in lattice QCD simulations in two (${N}_{f}=2$) and three (${N}_{f}=2+1$) flavor formulations. We analyze ${N}_{f}=2$ lattice scattering data using unitarized chiral perturbation theory, allowing not only for the extrapolation in mass but also in flavor, ${N}_{f}=2\to {N}_{f}\dots $

[Phys. Rev. Lett. 117, 122001] Published Thu Sep 15, 2016

]]>Researchers characterize the rotational jiggling of an optically levitated nanoparticle, showing how this motion could be cooled to its quantum ground state.

[Phys. Rev. Lett. 117, 123604] Published Thu Sep 15, 2016

]]>Fault-tolerant quantum computing in systems composed of both Majorana fermions and topologically unprotected quantum systems, e.g., superconducting circuits or quantum dots, is studied in this Letter. Errors caused by topologically unprotected quantum systems need to be corrected with error-correcti…

[Phys. Rev. Lett. 117, 120403] Published Wed Sep 14, 2016

]]>Quasiprobability representations, such as the Wigner function, play an important role in various research areas. The inevitable appearance of negativity in such representations is often regarded as a signature of nonclassicality, which has profound implications for quantum computation. However, litt…

[Phys. Rev. Lett. 117, 120404] Published Wed Sep 14, 2016

]]>Two of the key properties of quantum physics are the no-signaling principle and the Grover search lower bound. That is, despite admitting stronger-than-classical correlations, quantum mechanics does not imply superluminal signaling, and despite a form of exponential parallelism, quantum mechanics do…

[Phys. Rev. Lett. 117, 120501] Published Wed Sep 14, 2016

]]>Superconducting aluminum or superfluid helium could be used to detect superlight dark matter particles.

[Phys. Rev. Lett. 117, 121302] Published Wed Sep 14, 2016

]]>Matrix product states (MPSs) illustrate the suitability of tensor networks for the description of interacting many-body systems: ground states of gapped 1D systems are approximable by MPSs, as shown by Hastings [M. B. Hastings, J. Stat. Mech. (**2007**) P08024]. By contrast, whether MPSs and more genera…

[Phys. Rev. Lett. 117, 121601] Published Wed Sep 14, 2016

]]>We demonstrate that the coherence of a single mobile atomic qubit can be well preserved during a transfer process among different optical dipole traps (ODTs). This is a prerequisite step in realizing a large-scale neutral atom quantum information processing platform. A qubit encoded in the hyperfine…

[Phys. Rev. Lett. 117, 123201] Published Wed Sep 14, 2016

]]>High-frequency mechanical resonators subjected to low thermal phonon occupancy are easier to be prepared to the ground state by direct cryogenic cooling. Their extreme stiffness, however, poses a significant challenge for external interrogations. Here we demonstrate a superconducting cavity piezoele…

[Phys. Rev. Lett. 117, 123603] Published Wed Sep 14, 2016

]]>A quantum phase transition between two insulating phases of a magnetic topological insulator is observed experimentally by tuning the material’s chemical potential.

[Phys. Rev. Lett. 117, 126802] Published Wed Sep 14, 2016

]]>We report current-direction dependent or unidirectional magnetoresistance (UMR) in magnetic or nonmagnetic topological insulator (TI) heterostructures, ${\mathrm{Cr}}_{x}({\mathrm{Bi}}_{1-y}{\mathrm{Sb}}_{y}{)}_{2-x}{\mathrm{Te}}_{3}/({\mathrm{Bi}}_{1-y}{\mathrm{Sb}}_{y}{)}_{2}{\mathrm{Te}}_{3}$, that is several orders of magnitude larger than in other reported systems. From the magnetic field and temperatu…

[Phys. Rev. Lett. 117, 127202] Published Wed Sep 14, 2016

]]>We show how the thermodynamic properties of large many-body localized systems can be studied using quantum Monte Carlo simulations. We devise a heuristic way of constructing local integrals of motion of high quality, which are added to the Hamiltonian in conjunction with Lagrange multipliers. The gr…

[Phys. Rev. Lett. 117, 120402] Published Tue Sep 13, 2016

]]>We measured the power spectrum and two-point correlation function for the randomly fluctuating free surface on the downstream side of a stationary flow with a maximum Froude number ${F}_{\mathrm{max}}\approx 0.85$ reached above a localized obstacle. On such a flow the scattering of incident long wavelength modes is analog…

[Phys. Rev. Lett. 117, 121301] Published Tue Sep 13, 2016

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