Rotation is a ubiquitous concept in physics. A new approach shows how the concept of angular momentum spread among many particles can be simplified and approximated.

[Phys. Rev. X 6, 011012] Published Fri Feb 12, 2016

]]>Foams contain suspended bubbles and are therefore susceptible to degradation over time. Scientists show how a “suit of armor” that coats individual bubbles can stabilize them.

[Phys. Rev. X 6, 011010] Published Fri Feb 05, 2016

]]>Light-emitting diodes are in widespread use in both commercial and residential settings. New research shows that applying a small magnetic field to some devices can boost their luminescence efficiency.

[Phys. Rev. X 6, 011011] Published Fri Feb 05, 2016

]]>A robot group clusters together or disperses based on each robot’s reaction time for sensing light, a finding useful for search-and-rescue missions.

[Phys. Rev. X 6, 011008] Published Fri Jan 29, 2016

]]>Double-layer capacitors can be used to harness wind and solar energy, and now new measurements reveals the electrical double-layer structure of silica-electrolyte interfaces that controls capacitance.

[Phys. Rev. X 6, 011007] Published Thu Jan 28, 2016

]]>Many biological molecules exhibit rare events such as protein folding between long-lived states. A new approach allows the kinetics of these rare events to be efficiently simulated with readily achievable computational times.

[Phys. Rev. X 6, 011009] Published Thu Jan 28, 2016

]]>[Phys. Rev. X 6, 019901] Published Thu Jan 28, 2016

]]>Cerenkov radiation is ubiquitous in a range of applications from nuclear reactors to biological imaging. New work shows that the quantum attributes of the charged particles result in important changes to the traditional Cerenkov theory.

[Phys. Rev. X 6, 011006] Published Mon Jan 25, 2016

]]>Casimir and van der Waals forces, induced by dipolar fluctuations, are commonplace, and now a new study shows that fluctuations induced by monopolar charges can create similar or stronger forces in solid-state devices.

[Phys. Rev. X 6, 011004] Published Thu Jan 21, 2016

]]>The transition that an amorphous solid undergoes to become a fluid flow is central to many real-world applications such as landslides and earthquakes. Now, researchers model the stability of amorphous solids in three and four dimensions.

[Phys. Rev. X 6, 011005] Published Thu Jan 21, 2016

]]>Ensuring efficient pedestrian streams through transit corridors such as subway hallways is a problem of significant relevance to many cities. By modeling self-driven particles, scientists show that modulating the shape of a hallway’s walls might help to separate opposite pedestrian flows.

[Phys. Rev. X 6, 011003] Published Thu Jan 07, 2016

]]>The properties of human cells are determined by their mechanical environment, which they sense when they make contact with it. A new study shows how cells adhere to surfaces presenting heterogeneous nanomechanical environments.

[Phys. Rev. X 6, 011001] Published Tue Jan 05, 2016

]]>A quantum system can jump into its ground state by emitting a photon. Now, scientists produce a superposition of ground and excited states by just measuring the emitted light.

[Phys. Rev. X 6, 011002] Published Tue Jan 05, 2016

]]>Researchers explore the limits of quantum theory using pairs of entangled photons and find results consistent with quantum predictions.

[Phys. Rev. X 5, 041052] Published Wed Dec 30, 2015

]]>Molecular nitrogen plays a role in the assembly of prebiotic molecules, and it protects humans from the Sun’s extreme ultraviolet radiation. Researchers investigate, for the first time, the ultrafast molecular dynamics of nitrogen as it disassociates.

[Phys. Rev. X 5, 041053] Published Wed Dec 30, 2015

]]>Optomechanics, which refers to the interplay of light and nanomechanics, has widespread applications in sensing and quantum optics. Researchers demonstrate that an optomechanical system based on single-crystal diamond nanobeams can undergo large self-oscillations.

[Phys. Rev. X 5, 041051] Published Tue Dec 29, 2015

]]>Conventional electric circuits use electrons as information carriers, a process that dissipates vast quantities of waste heat. A new design for a spin-wave diode, which produces no Joule heating, is presented.

[Phys. Rev. X 5, 041049] Published Mon Dec 28, 2015

]]>Novel topological phenomena are believed to arise in systems driven out of equilibrium. Now, researchers make a key step toward realizing such phenomena and establish the requirements for obtaining Floquet insulator steady states.

[Phys. Rev. X 5, 041050] Published Mon Dec 28, 2015

]]>Many-body localization leads to the breakdown of ergodicity in quantum systems and defies description in terms of equilibrium statistical mechanics. Researchers introduce an order parameter that makes it possible to probe how ergodicity and thermalization break down due to many-body localization.

[Phys. Rev. X 5, 041047] Published Wed Dec 23, 2015

]]>Two-dimensional Mott insulators allow for a remarkable “deconfined” quantum phase transition. A new theoretical and computational study shows that this controversial critical point may be even stranger than previously thought.

[Phys. Rev. X 5, 041048] Published Wed Dec 23, 2015

]]>Topological effects persist in Weyl semimetals, and now two experiments show how Fermi arcs lead to nonlocal currents in Weyl semimetal samples already at the semiclassical level.

[Phys. Rev. X 5, 041046] Published Mon Dec 21, 2015

]]>A new metamaterial acts like a cloak over a wide range of microwave frequencies.

[Phys. Rev. X 5, 041045] Published Fri Dec 18, 2015

]]>Theorists demonstrate a quantum variant of the Kolmogorov-Arnold-Moser theorem, a theorem in classical mechanics that concerns the crossover between integrability and chaos. Integrability breaking in the Lieb-Liniger model, a model describing one-dimensional Bose gases, leads to a deformation, not destruction, of the model’s conserved quantities.

[Phys. Rev. X 5, 041043] Published Wed Dec 16, 2015

]]>Correlated quantum many-body systems appear in physics, chemistry, and biology. Researchers simulate and explore such systems using an experimentally controlled superconducting quantum device.

[Phys. Rev. X 5, 041044] Published Wed Dec 16, 2015

]]>Majorana particles, which are their own antiparticles and whose recent detection in solid-state systems remains controversial, are expected to play an important role in future quantum computing. Now, scientists predict that graphene may host Majorana particles.

[Phys. Rev. X 5, 041042] Published Tue Dec 15, 2015

]]>Error correction is critical in topological quantum computation, but it restricts the quantum gates that can be easily performed. A proposed model shows how to correct errors and perform complex gates by braiding in realistic qubit systems that support non-Abelian parafermions.

[Phys. Rev. X 5, 041040] Published Mon Dec 14, 2015

]]>Modeling systems with a large number of interacting electrons is critical to understanding the physical properties of materials and molecules of interest to chemists and physicists. Researchers model a system using a range of numerical techniques and compare results in order to find sources of uncertainty and establish benchmarks.

[Phys. Rev. X 5, 041041] Published Mon Dec 14, 2015

]]>Fault-tolerant quantum computation has been a long-standing goal in many fields of physics. A new model shows how logical qubits can be encoded using anyon excitations from Majorana fermions arranged on a two-dimensional lattice.

[Phys. Rev. X 5, 041038] Published Thu Dec 10, 2015

]]>Copying information is fundamental in both nature and human industries. Researchers show how the accuracy of a simple copying process is related to thermodynamics.

[Phys. Rev. X 5, 041039] Published Thu Dec 10, 2015

]]>The act of a quantum measurement reduces the uncertainty in the motion of a vibrating membrane below the fundamental quantum limit.

[Phys. Rev. X 5, 041037] Published Mon Dec 07, 2015

]]>A proof-of-principle experiment allows single photons to travel in only one direction through an optical fiber.

[Phys. Rev. X 5, 041036] Published Fri Dec 04, 2015

]]>Theorists studying unexpected quantum states of matter show that the second-neighbor Kitaev can explain materials that are in close proximity to a spin-liquid state.

[Phys. Rev. X 5, 041035] Published Tue Dec 01, 2015

]]>Time-reversal symmetry is fundamental to condensed matter physics, and now researchers show how time reversal can be applied locally, using a tensor network representation, and how time-reversal twists can be used to detect topological order.

[Phys. Rev. X 5, 041034] Published Mon Nov 30, 2015

]]>Glasses remain a poorly understood material despite their widespread use. A study of the macroscopic elastic properties of a colloidal-glass former during vitrification offers new insights.

[Phys. Rev. X 5, 041033] Published Wed Nov 25, 2015

]]>Researchers use ideas generated in the study of quantum entanglement to guide the construction of new impurity solvers, enabling analysis of substantially more complex and realistic problems within the cluster dynamical mean-field-theory framework.

[Phys. Rev. X 5, 041032] Published Tue Nov 24, 2015

]]>Topological insulators possess properties of both conductors and insulators. A theoretical study demonstrates that the surface state of a Fu-Kane-Mele topological insulator can access all of the other surface states of the material.

[Phys. Rev. X 5, 041031] Published Fri Nov 20, 2015

]]>Chaos is a fundamental aspect of many fields of nuclear and atomic physics. Scientists use collisions among magnetic rare-earth atoms to investigate quantum chaos.

[Phys. Rev. X 5, 041029] Published Thu Nov 19, 2015

]]>Cortical neural circuits have been hypothesized to operate in a regime termed the “edge of chaos.” A new theoretical study puts this regime in a more biologically plausible perspective.

[Phys. Rev. X 5, 041030] Published Thu Nov 19, 2015

]]>The transition between a superfluid and a normal fluid in two dimensions can be understood in terms of the proliferation of topological defects. Now, scientists theoretically analyze such phase transitions in the far-from-equilibrium context of a quantum fluid of exciton polaritons.

[Phys. Rev. X 5, 041028] Published Tue Nov 17, 2015

]]>Modulating the phase of electromagnetic waves has many applications in photonic research. A new mechanism allows a thin graphene metasurface to reliably achieve an extremely large phase modulation in THz radiation.

[Phys. Rev. X 5, 041027] Published Mon Nov 16, 2015

]]>Black hole horizons have been shown to have characteristic entropies and temperatures. A new investigation shows similarities between the entropy of a black hole and a metallic state of high-temperature superconductors.

[Phys. Rev. X 5, 041025] Published Fri Nov 13, 2015

]]>Water, plasmas, and laser light can all exhibit instabilities. Experiments in two different areas of wave physics are used to investigate the creation and annihilation dynamics of superregular breather waves, which combine to form an instability.

[Phys. Rev. X 5, 041026] Published Fri Nov 13, 2015

]]>Coupling the frequency of an electromagnetic cavity to the square of mechanical displacement of the cavity structure has been proposed for realizing quantum nondemolition measurements. Such measurement systems are now one step closer with the realization of a tunable microscale photonic crystal cavity with coupling that is some 5 orders of magnitude larger than in conventional Fabry-Pérot resonators.

[Phys. Rev. X 5, 041024] Published Thu Nov 12, 2015

]]>Spintronics devices often use the accumulation of spins, probed by magnetoresistance, to convey information, and now researchers identify the origin of junction magnetoresistance in artificially engineered oxide heterostructures.

[Phys. Rev. X 5, 041023] Published Wed Nov 11, 2015

]]>Interactions between molecules and light modes can alter the chemical structures of molecules. By examining strong coupling from a microscopic perspective it is possible to predict the modifications that molecules will undergo.

[Phys. Rev. X 5, 041022] Published Mon Nov 09, 2015

]]>The Meissner effect, which explains the levitation of magnetic objects, involves the expulsion of external magnetic flux from a superconductor. Now, researchers show that the inverse effect can also occur in which external magnetic flux is amplified.

[Phys. Rev. X 5, 041021] Published Fri Nov 06, 2015

]]>Superconducting qubit experiments cannot be conducted without nonreciprocal devices such as circulators and directional amplifiers. Researchers show that both of these kinds of devices can be realized using a single Josephson circuit.

[Phys. Rev. X 5, 041020] Published Thu Nov 05, 2015

]]>Superconducting cuprates are of great interest in condensed-matter physics, and now a new study shows that another transition-metal oxide, Sr${}_{2}$IrO${}_{4}$, may be analogous to cuprates in its high-temperature superconductivity.

[Phys. Rev. X 5, 041018] Published Wed Nov 04, 2015

]]>Many of tomorrow’s photonic devices, including optical biosensors, may rely on light signals with highly particular polarization properties. A new experiment shows that an ultrathin layer of gold particles can selectively absorb or reflect a light beam depending on its polarization handedness.

[Phys. Rev. X 5, 041019] Published Wed Nov 04, 2015

]]>Previous studies have shown that single nuclear spins and nuclear spin pairs can be detected. Scientists analyze time-periodic sensing protocols using Floquet theory, a powerful new method for relating experimental features to the characteristics of the detected spin or small cluster of spins.

[Phys. Rev. X 5, 041016] Published Fri Oct 30, 2015

]]>Because photons interact weakly with themselves and experience low decoherence, they are a promising avenue for quantum information science. Theorists show how the temporal modes of single-photon states can form an alphabet for communication across a quantum information network.

[Phys. Rev. X 5, 041017] Published Fri Oct 30, 2015

]]>Particle interference is a critical component of optical quantum computing and communication. Now, researchers examine multiphoton quantum interference both theoretically and experimentally by manipulating the distinguishability of photons.

[Phys. Rev. X 5, 041015] Published Tue Oct 27, 2015

]]>High-resolution tracking of the population abundances in a simple, closed microbial ecosystem shows that the intrinsic dynamics of the system are strongly deterministic.

[Phys. Rev. X 5, 041014] Published Mon Oct 26, 2015

]]>High-temperature superconductivity—the property of zero electrical resistance at relatively high temperature—is manifested in very limited classes of materials. An examination of the unique relationship between electronic structures and lattice structural units of the two known classes of high-temperature superconductors helps to identify possible new classes of these materials.

[Phys. Rev. X 5, 041012] Published Fri Oct 23, 2015

]]>Exotic excitations known as anyons are found in fractional quantum Hall states. Now, a systematic method establishes that certain symmetric theories of anyons cannot be realized in two dimensions.

[Phys. Rev. X 5, 041013] Published Fri Oct 23, 2015

]]>Quantum effects such as coherence and entanglement increase a system’s ability to store energy.

[Phys. Rev. X 5, 041011] Published Thu Oct 22, 2015

]]>Secure cryptography has been a long-standing goal of quantum applications. Now, researchers experimentally show how a quantum setup can transmit a pattern of 1s and 0s over a 25-km optical fiber by interfering two independent lasers.

[Phys. Rev. X 5, 041009] Published Wed Oct 21, 2015

]]>Quantum technology that enables two distant parties to securely communicate is of great interest in cryptography. New research shows how implementations of quantum key distribution can be significantly simplified by not co-transmitting a local oscillator reference between the two communicating parties.

[Phys. Rev. X 5, 041010] Published Wed Oct 21, 2015

]]>Quantum key distribution, a process employed in encrypted transactions, relies on Einstein-Podolsky-Rosen steering when one party has untrusted devices. For the first time, a formal framework of steering as a physical resource is presented.

[Phys. Rev. X 5, 041008] Published Thu Oct 15, 2015

]]>A theoretical analysis quantifies the technical resources required to build a quantum computer based on photons.

[Phys. Rev. X 5, 041007] Published Wed Oct 14, 2015

]]>The evolution of an isolated quantum system has applications in many fields of atomic physics, condensed matter physics, and cosmology. A theoretical study shows how an ensemble of interacting quantum spins exhibits different relaxation dynamics depending on the energy of the prepared initial states.

[Phys. Rev. X 5, 041005] Published Mon Oct 12, 2015

]]>Quantum states play key roles in advanced cryptographic methods. Now, experiments show that quantum state tomography can be optimized by employing certain mathematical constructions.

[Phys. Rev. X 5, 041006] Published Mon Oct 12, 2015

]]>There are only a handful of materials in nature that exhibit sequential temperature-dependent transitions from a paramagnetic metal to a ferromagnetic metal phase and then onto a ferromagnetic insulator phase. Now, scientists have used spectroscopy and theoretical calculations to reveal details about such transitions in polycrystalline K${}_{2}$Cr${}_{8}$O${}_{1}6$.

[Phys. Rev. X 5, 041004] Published Fri Oct 09, 2015

]]>Studies of the fractional quantum Hall effect rely on understanding the Hamiltonians whose eigenstates are described by its wave functions. A geometric approach is used to calculate the Hamiltonian pseudopotentials for electron gases with arbitrary geometries.

[Phys. Rev. X 5, 041003] Published Thu Oct 08, 2015

]]>A crystal cavity for light and sound has been chilled close to its motional ground state.

[Phys. Rev. X 5, 041002] Published Tue Oct 06, 2015

]]>Magnetic fields play roles in a variety of scientific and medical applications. Using solid-state spins in diamond, researchers experimentally demonstrate the measurement of magnetic fields as small as 100 fT in a tiny sensor volume.

[Phys. Rev. X 5, 041001] Published Mon Oct 05, 2015

]]>Heat machines on the atomic scale are surprisingly similar to their macroscopic classical counterparts. Theorists show that all different engine types become thermodynamically equivalent in the quantum regime.

[Phys. Rev. X 5, 031044] Published Tue Sep 29, 2015

]]>The goal of achieving quantum computation requires overcoming the limitation of quantum noise. A new approach shows how noisy local information about noise can be used to reliably correct errors for an ensemble of qubits on a lattice.

[Phys. Rev. X 5, 031043] Published Mon Sep 28, 2015

]]>Characterizing the entangled states of quantum objects is both time and resource demanding. Now, researchers experimentally demonstrate an optical setup for partially characterizing entangled states in a much more efficient manner.

[Phys. Rev. X 5, 031042] Published Thu Sep 24, 2015

]]>Fast-rotating molecules spun up by a laser pulse maintain their alignment despite collisions.

[Phys. Rev. X 5, 031041] Published Wed Sep 23, 2015

]]>There is interest in modulating emergent phases such as magnetism and superconductivity on short time scales. New theoretical results reveal how the melting of magnetic order proceeds along different pathways depending on whether electrons behave like localized magnetic moments or coherent quasiparticles.

[Phys. Rev. X 5, 031039] Published Fri Sep 18, 2015

]]>Quantum computing promises to be more efficient and significantly faster than today’s classical computing. Researchers compare the performance of a quantum annealer with that of classical algorithms for the first time on hard spin-glass problems.

[Phys. Rev. X 5, 031040] Published Fri Sep 18, 2015

]]>The definition of quantum work differs markedly from the definition found in classical mechanics textbooks. Now, by showing that quantum work distributions can be understood as interference patterns between classical trajectories, researchers bridge the gap between classical and quantum notions of work.

[Phys. Rev. X 5, 031038] Published Thu Sep 17, 2015

]]>Many realistic networks, including biological ones, are driven by noise, which can generate sudden changes in system behavior. Using a scalable algorithm for controlling the response to noise in complex biological systems, researchers identify gene targets for new cancer therapies.

[Phys. Rev. X 5, 031036] Published Wed Sep 16, 2015

]]>Analyzing changes in resistivity is one component of condensed-matter physics research that has applications in the electronics industry. Now, researchers experimentally show that the resistivity of a Cd${}_{3}$As${}_{2}$ crystal can be modulated by the geometry of the material’s Fermi surface.

[Phys. Rev. X 5, 031037] Published Wed Sep 16, 2015

]]>Novel electronic devices of the future may rely on the magnetoelectric effect, which researchers now show can be controlled in a $3d$ transition metal via Zn doping.

[Phys. Rev. X 5, 031034] Published Tue Sep 15, 2015

]]>High-temperature superconductivity has numerous applications in industry, yet the origin of this phenomenon remains controversial. A new study reveals how doped LiFe${}_{1-x}$Co${}_{x}$As exhibits a range of transition temperatures and crossovers between a Fermi-liquid state and a non-Fermi-liquid state.

[Phys. Rev. X 5, 031035] Published Tue Sep 15, 2015

]]>The dynamical behavior of quantum systems is relevant to quantum information processing. A new theoretical model describes a phase transition from many-body localized states, in which quantum information is accessible, to thermal states, in which such information is lost in the dynamics.

[Phys. Rev. X 5, 031032] Published Mon Sep 14, 2015

]]>Developments in ultracold atomic experimental techniques highlight fundamental questions of whether quantum systems obey thermodynamics and statistical mechanics when isolated from their environment. A numerical technique is used to study phase transitions between thermal quantum fluids that obey thermodynamics and frozen quantum glasses that do not.

[Phys. Rev. X 5, 031033] Published Mon Sep 14, 2015

]]>Surface acoustic waves may work as a “quantum bus” that carries information to different parts of a quantum computer.

[Phys. Rev. X 5, 031031] Published Thu Sep 10, 2015

]]>Researchers propose an approach to safeguard optical quantum key distribution systems against Trojan-horse attacks.

[Phys. Rev. X 5, 031030] Published Wed Sep 09, 2015

]]>Theorists show that large photon fluxes can result in the breakdown of photon blockade, an analogy to Coulomb blockade for quantum-well electrons. This breakdown is due to a quantum phase transition in zero dimensions.

[Phys. Rev. X 5, 031028] Published Tue Sep 08, 2015

]]>Solar cell technology benefits from increased photocurrents. New research uses transformation optics to preferentially concentrate light in hotspots in a metal grating.

[Phys. Rev. X 5, 031029] Published Tue Sep 08, 2015

]]>Quantum phenomena include the fractional quantum Hall effect, whose quasiparticle is the composite fermion. Theorists show that composite fermions possess different quantum numbers than the electrons or holes they were derived from.

[Phys. Rev. X 5, 031027] Published Wed Sep 02, 2015

]]>While manufacturing limitations are imposing constraints on Moore’s law, researchers are searching for novel computing architectures based on quantum-mechanical effects. However, it remains to be shown that quantum annealing techniques consistently outperform classical simulated annealing to minimize optimization problems.

[Phys. Rev. X 5, 031026] Published Tue Sep 01, 2015

]]>Spherical particles are excellent test beds for studies of interparticle collisions. Researchers use tiny spheres to investigate how energy driving can yield the coexistence of a solid and liquid phase.

[Phys. Rev. X 5, 031025] Published Fri Aug 28, 2015

]]>Quantum computing requires stable qubits that can hold information for long periods of time. Researchers assemble a hybrid double quantum dot that is both scalable and possesses a long-lived quantum memory.

[Phys. Rev. X 5, 031024] Published Thu Aug 27, 2015

]]>Weyl points can be thought of as magnetic monopoles in momentum space that always appear in pairs. Magnetoresistance measurements indicate the existence of the long-anticipated chiral anomaly in Weyl semimetal TaAs single crystals.

[Phys. Rev. X 5, 031023] Published Mon Aug 24, 2015

]]>An oscillatory motion dramatically reduces the number of contaminant molecules at the interface between two surfaces.

[Phys. Rev. X 5, 031020] Published Fri Aug 21, 2015

]]>Advanced imaging and spectroscopy techniques make it possible to investigate electronic states in superconductors. Scanning tunneling microscopy shows that time-reversal symmetry is broken at the crystallographic boundaries of superconducting FeSe.

[Phys. Rev. X 5, 031022] Published Fri Aug 21, 2015

]]>X-ray radiation impinging on molecules has many medical applications. X-ray-induced electron dynamics in carbon disulfide is studied in order to probe nuclear and electronic degrees of freedom.

[Phys. Rev. X 5, 031021] Published Thu Aug 20, 2015

]]>Heat engines translate thermal energy into useful mechanical work. New results show how the power and efficiency of miniaturized heat engines are related, which paves the way for studies of even smaller systems that experience quantum effects.

[Phys. Rev. X 5, 031019] Published Wed Aug 19, 2015

]]>Systems characterized by interconnected nodes are common in both nature and society. A theoretical method yields exact equations to describe the pruning of networks based on each node’s number of neighbors.

[Phys. Rev. X 5, 031017] Published Tue Aug 18, 2015

]]>Measurement uncertainty is fundamental to all fields of science. The lower limit on measurement uncertainty for an optical signal composed of multiple entangled modes is analytically determined.

[Phys. Rev. X 5, 031018] Published Tue Aug 18, 2015

]]>Understanding the electronic structure of molecules has been a long-standing goal in molecular physics. A new proposal uses artificial benzene molecules to image three-dimensional molecular orbitals.

[Phys. Rev. X 5, 031016] Published Mon Aug 17, 2015

]]>Light-matter coupling is an ongoing investigation in modern physics and is expected to play a role in quantum information applications. Using single-atom-controlled samples of ultracold rubidium-87 coupled to Rydberg states, scientists show that many-body systems of various sizes can be coherently manipulated as a single “superatom.”

[Phys. Rev. X 5, 031015] Published Wed Aug 12, 2015

]]>Chemical fluctuations within cells affect biological functioning. An accurate mathematical theory now permits a quantitative understanding of intracellular chemical fluctuations and their impact on the probabilistic behaviors of cells.

[Phys. Rev. X 5, 031014] Published Mon Aug 10, 2015

]]>Accelerating electrons to relativistic energies has applications in time-resolved electron diffraction. Experiments and simulations show that inhomogeneities in a laser’s electric field affect the quality of the accelerated electron beam.

[Phys. Rev. X 5, 031012] Published Fri Jul 31, 2015

]]>Weyl fermions possess exotic properties and can act like magnetic monopoles. Researchers show that TaAs is a Weyl semimetal, demonstrating for the first time that Weyl semimetals can be identified experimentally.

[Phys. Rev. X 5, 031013] Published Fri Jul 31, 2015

]]>In everyday life, if sound propagates from one location to another, it can propagate backwards just as easily. However, theorists show that it is possible to harness the radiation pressure interaction between light and matter to produce unidirectional sound propagation.

[Phys. Rev. X 5, 031011] Published Tue Jul 28, 2015

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