Experiments show for the first time the quantization of exciton energies in a 2D semiconductor exposed to a high magnetic field, setting the stage for explorations of quantized excitons in the presence of strong Coulomb interactions. | Continue reading
We present a photonic integrated circuit architecture for a quantum programmable gate array (QPGA) capable of preparing arbitrary quantum states and operators. The architecture consists of a lattice of phase-modulated Mach-Zehnder interferometers, which perform rotations on path- … | Continue reading
Conventional sound barriers impede airflow at the same time. Recent advances in acoustic metasurfaces provide a solution for air-permeable barriers utilizing the Fano-like interference. While the mechanism of Fano-like interference implies that such a realized device serves a nar … | Continue reading
The authors provide an algorithm to incorporate quantum annealing into automated materials discovery. Their scheme can be used to design complex structures of wavelength selective radiators showing much better agreement with the thermal atmospheric transparency window. | Continue reading
It is shown that the magnetic-field coils of a stellarator can, at least in principle, be substantially simplified by the use of permanent magnets. Such magnets cannot create toroidal magnetic flux, but they can be used to shape the plasma and thus to create poloidal flux and rot … | Continue reading
The existence of ideal quantum measurements is one of the fundamental predictions of quantum mechanics. In theory, an ideal measurement projects a quantum state onto the eigenbasis of the measurement observable, while preserving coherences between eigenstates that have the same e … | Continue reading
A model is developed for liquid drop impact on a solid surface that captures the thin film gas flow beneath the drop, even when the film's thickness is below the mean free path in the gas so that gas kinetic effects (GKE) are important. Simulation results agree with experiments, … | Continue reading
An extensive theoretical and experimental investigation has been conducted on fermion-pair condensation and exciton condensation as distinct classes of Bose-Einstein-like condensation. In this Rapid Communication, the existence of a fermion-exciton condensate---a single quantum s … | Continue reading
A rare kind of nuclear spinning motion has been detected in an isotope of gold. | Continue reading
Topological Weyl semimetals (WSMs) have attracted widespread interest due to the chiral Weyl fermions and surface Fermi arcs that enable unique optical and transport phenomena. In this work, we present angle-resolved Raman spectroscopy of TaP, a prototypical noncentrosymmetric WS … | Continue reading
A holographic technique confines excited Rydberg atoms in the central dark region of a 3D light-intensity pattern. | Continue reading
The world's largest free-floating soap bubbles can encompass a small automobile and span nearly 100 square meters, despite being only microns thick. Experiments show that long, polydisperse polymer chains provide extensional properties during bubble formation and reduce gravitati … | Continue reading
The Borexino experiment has doubled its data on neutrinos generated inside Earth, providing new constraints on geological models of the mantle. | Continue reading
Complex distribution networks are pervasive in biology. Examples include nutrient transport in the slime mold Physarum polycephalum as well as mammalian and plant venation. Adaptive rules are believed to guide development of these networks and lead to a reticulate, hierarchically … | Continue reading
A strand of spaghetti changes shape as it is cooked. This paper proposes a theory that includes a time-dependent curvature, and models the evolution of the system based on previous observations. The authors compare their results with tabletop experiments and find good agreement. | Continue reading
An optical clock based on an array of individually trapped atoms provides a new twist in atom-based timekeeping. | Continue reading
Temporal multiplexing provides an efficient and scalable approach to realize a quantum random walk with photons that can exhibit topological properties. But two-dimensional time-multiplexed topological quantum walks studied so far have relied on generalizations of the Su-Shreiffe … | Continue reading
By measuring the forces that cause floating objects to drift toward each other, researchers hope to better understand the interactions that cause particles to self-assemble in fluids. | Continue reading
The change in entropy of a system that is transferred between two states at different temperatures is measured in a two-dimensional plasma crystal experiment. One- and especially two-component dust clusters are confined in the plasma sheath and heated to different temperatures us … | Continue reading
Photons entangled in high dimensions are more resilient to noise, making them ideal for quantum communication applications. | Continue reading
This Letter reports the first spin tune measurement at high energies (24 and 255 GeV) with a driven coherent spin motion. To maintain polarization in a polarized proton collider, it is important to know the spin tune of the polarized proton beam, which is defined as the number of … | Continue reading
An array of nine strongly interacting Rydberg atoms is used for a proof-of-principle demonstration of neural-network quantum state reconstruction. | Continue reading
Experiments reveal changes in the electronic state of the iron-based superconductor FeSe during the emergence of nematicity, a fourfold rotational symmetry breaking that arises close to the onset of superconductivity. | Continue reading
A hollow spherical bubble containing thousands of spin-aligned triplet positronium (Ps) atoms in superfluid liquid $^{4}\mathrm{He}$ would be stable against breakup into smaller bubbles, and the Ps would form a Bose-Einstein condensate (BEC) with a number density of $\ensuremath{ … | Continue reading
A calculation shows that an elusive, isolated quantum time crystal may not be far from reality. | Continue reading
Implanted medical devices often transmit wireless signals to communicate with external equipment, but the efficiency of signal transmission is limited by internal reflection at the surface of the body. This work presents an approach to greatly enhance transmission, through the de … | Continue reading
Researchers have observed the decay of a topological knot defect in a quantum gas. | Continue reading
The recently established agreement between experiment and theory for the $g$ factors of lithiumlike silicon and calcium ions manifests the most stringent test of the many-electron bound-state quantum electrodynamics (QED) effects in the presence of a magnetic field. In this Lette … | Continue reading
Dynamic interactions between nanosecond shockwave induced by leaky Rayleigh wave and evanescent wave at water-glass boundaries are investigated experimentally and numerically. This interaction generates the maximum impulsive tension in the solid, leading to circular crack formati … | Continue reading
We have directly imaged the spontaneous formation of metastable surface phase domains on GaAs(001) during Langmuir evaporation. Eventually, these metastable phases transform to the thermodynamically stable parent phase, producing a dynamic phase coexistence with a temperature dep … | Continue reading
The liquid layer that forms between ice and any object gliding along its surface is far thinner and more viscous than imagined, setting the stage for new ways of thinking about why ice is so slippery. | Continue reading
Exclusive cross sections and momentum distributions have been measured for quasifree one-neutron knockout reactions from a $^{54}\mathrm{Ca}$ beam striking on a liquid hydrogen target at $\ensuremath{\sim}200\text{ }\text{ }\mathrm{MeV}/u$. A significantly larger cross section to … | Continue reading
If a wormhole smoothly connects two different spacetimes, then the flux cannot be separately conserved in any of these spaces individually. Then objects propagating in the vicinity of a wormhole in one space must feel the influence of objects propagating in the other space. We sh … | Continue reading
New results from the GlueX collaboration probe the gluonic structure of the proton. | Continue reading
Among the prominent candidates for dark matter are bosonic fields with small scalar couplings to the standard-model particles. Several techniques are employed to search for such couplings, and the current best constraints are derived from tests of gravity or atomic probes. In exp … | Continue reading
A proposed device could detect the hypothesized dark matter particle in a mass regime not probed by other devices. | Continue reading
Simulations show that competing models of dark matter produce primordial star-forming regions that look very different from one another. | Continue reading
In a seminal article, Fano predicts that absorption of light occurs preferably with increase of angular momentum. We generalize Fano's propensity rule to laser-assisted photoionization, consisting of absorption of an extreme-ultraviolet photon followed by absorption or emission o … | Continue reading
We provide the first example of local quantum energy conditions in quantum field theories that are not Lorentz invariant. We focus on field theories in two dimensions with infinite-dimensional symmetries, like the ones governed by the Bondi--van der Burg--Metzner--Sachs group tha … | Continue reading
We experimentally demonstrate the generation of a three-photon discrete-energy-entangled $W$ state using multiphoton-pair generation by spontaneous four-wave mixing in an optical fiber. We show that, by making use of prior information on the photon source, we can verify the state … | Continue reading
It's now possible to harvest energy at the mesoscopic scale by exploiting the resonant tunneling in a nanoscale thermoelectric device consisting of two quantum dots. | Continue reading
We investigate opportunities and challenges for improving unsupervised machine learning using four common strategies with a long history in physics: divide and conquer, Occam's razor, unification, and lifelong learning. Instead of using one model to learn everything, we propose a … | Continue reading
Urban outputs often scale superlinearly with city population. A difficulty in understanding the mechanism of this phenomenon is that different outputs differ considerably in their scaling behaviors. Here, we formulate a physics-based model for the origin of superlinear scaling in … | Continue reading
This Letter proposes a realistic implementation of the curved relativistic mirror concept to reach unprecedented light intensities in experiments. The scheme is based on relativistic plasma mirrors that are optically curved by laser radiation pressure. Its validity is supported b … | Continue reading
A new design for a cavity spintronic device obtains a strong photon-magnon coupling with a magnet that is over 1000 times smaller than previously used magnets. | Continue reading
A proposed hydrogen-rich solid would superconduct above the boiling point of water---though the material would need to be subjected to a colossal pressure. | Continue reading