When determining the authorship list for your next paper, be generous yet disciplined.

A new Collection by the Physical Review journals celebrates the 50th anniversary of the discovery of asymptotic freedom in quantum chromodynamics (QCD)—the theoretical basis for the strong force of nature that binds quarks and gluons into hadrons.

The American Physical Society (APS) is pleased to announce that it will begin sponsoring Astrobites, a daily astrophysical literature journal written by graduate students in astronomy. This mutually beneficial collaboration aims to enhance the dissemination of research, educational resources, and career insights in the field of astronomy and astrophysics.

Reversible to irreversible (R-IR) transitions have been found in a wide variety of both soft and hard matter periodically driven collectively interacting systems that, after a certain number of driving cycles, organize into either a reversible state where the particle trajectories repeat during every or every few cycles or into a chaotic motion state. An overview of R-IR transitions including recent advances in the field is followed by a discussion of how the general framework of R-IR transitions could be applied to a much broader class of nonequilibrium systems in which periodic driving occurs, including not only soft and hard condensed matter systems, but also astrophysics, biological systems, and social systems.

A topologically stable line defect, called a skyrme line, is shown to exist in ferroelectric materials. Unusually, their topological charge can fractionalize. The properties, creation, and stability of these fractional defects are studied.

This article shows a quantum phase transition in a quasi-one-dimensional zigzag-chain Ising antiferromagnet CaCoV${}_2$O${}_7$ with a nontrivial exponent $\varphi$ $\approx$ 1/6 that results from the onset of spin-orbit coupling and the competing exchange interactions $J$${}_1$ and $J$${}_2$ of the zigzag spin chain.

A study explores the shepherding control problem, where one complex multiagent system (the herders) controls the collective dynamics of another complex multiagent system (the targets). The findings reveal that for noncohesive targets and herders with limited sensing capability, there exists a critical density threshold for the targets below which shepherding becomes significantly more challenging. This phenomenon is explained through the percolation of a suitably defined “herdability” graph.

High-field magnetotransport and Hall effect measurements on the van der Waals ferromagnet Fe${}_{3-x}$GeTe${}_2$ reveals a dramatic change in the quasiparticle character below 80 K and indicate electronmagnon scattering with an atypical temperature dependence, supporting the presence of Kondo-lattice behavior in this $d$-electron system.

A reinforcement learning-based method is introduced that adaptively determines the optimal playing sequence in Parrondo’s games, enhancing profit outcomes.

Transfer entropy is the primary method for determining the information flow from a driver to a target time series. A study shows how it can be decomposed into pure two-body effects and higher-order ones, the latter consisting of information shared with the driver with the rest of the environment, which can be synergistic or redundant. An application to El Niño and the Southern Oscillation is presented.

The anticipated chiral-magnetic-effect (CME)-related charge separation was not measured to be larger in ${}_{44}^{96}$Ru + ${}_{44}^{96}$Ru than in ${}_{40}^{96}$Zr + ${}_{40}^{96}$Zr collisions because the flow-induced backgrounds do not fully cancel due to nuclear structure differences between the two isobar nuclei. Properly taking this, as well as the next-level nonflow-related backgrounds, into account, the charge separation results are consistent between the isobar systems, and an upper limit of 10% of the CME signal is extracted at a 95% confidence level.

The weakly nonlinear regime of a one-dimensional photon superfluid is characterized by the emergence of bound Bogoliubov quasiparticles, secondary collective excitations originating from nonresonant interactions between Bogoliubov modes. These processes, which are revealed by a structure of additional branches in the dispersion relation, do not depend on the specific superfluid under consideration but are inherent in the nonlinear dynamics of collective excitations.

A machine-learning-based quantum error-correction decoder is trained and implemented on IBM quantum hardware through cloud access, demonstrating the capability to accurately decode complex errors on experimental devices.

Universality is at the heart of an equilibrium phase transition. This article unveils the emergence of universal quantum critical behavior in quench dynamics.

An inherent pairing ratio in spontaneous four-wave mixing within an atomic ensemble represents the ratio of temporally correlated biphotons generated through stimulated four-wave mixing to total scattered photons in a specific direction. The experiment demonstrates ultrabright biphoton generation and shows that this pairing ratio improves with increased atomic ensemble density.

Polar activity is shown to induce a progressive local deformation of linear polymer chains, making a clear distinction between head and tail, while the overall chain conformation becomes more compact.

A universal set of microwave-driven quantum gates is implemented on a two-qubit trapped-ion quantum register, and the ability to carry out arbitrary circuits is demonstrated using the cycle benchmarking protocol. The structure can serve as a universal quantum computation register for the quantum CCD architecture of the trapped-ion quantum computer.

A study examines directional light-matter interaction within quantum-dot embedded, topological photonic crystal waveguides, comparing their performance to conventional line defect waveguides. The findings indicate that topological waveguides exhibit weaker directional coupling, even with the application of state-of-the-art inverse design methods.

Nuclear motion is responsible for a significant increase of the two-photon ionization delays in molecules due to the temporal confinement of the ejected electron between two nuclei.

The transition from edge-dominated to bulk-dominated quantum interference patterns of supercurrents in a quantum anomalous Hall-based Josephson junction is investigated. An anomalous Fraunhofer-like pattern is observed due to the bulk carriers induced by magnetic domains, even when the chemical potential resides within the bulk gap.

The calibration-control dilemma is addressed in unstable dynamical systems where control distorts the determination of the parameters that are needed for control implementation, leading to large, unwanted fluctuations. By integrating parameter calibration and control within a data assimilation framework, the proposed method achieves performance comparable to systems with fully known parameters, allowing control of most complex systems for which equations or parameters are unknown.

Learning the multiscale structural complexity can unveil off-diagonal long-range order solely through experimentally available descriptors.

Buckling instabilities can be seen in systems ranging from biological flagella to cables dropped to the ocean floor: the coiling of a dropped chain or a falling jet of honey are familiar examples. A chain of sticky bubbles is presented that rise due to buoyancy and buckle due to hydrodynamic effects.

A protocol to reliably demonstrate Kondo behavior in tunneling spectroscopy is presented, employing a Hurwitz line shape to correctly describe the Fermi-Dirac-broadened Kondo peak, as well as a recently derived equation for the intrinsic temperature dependence of the Kondo resonance.

A scalable Floquet scheme for the quantum simulation of the real-time dynamics in a ℤ${}_2$ lattice gauge theory is proposed, considering periodically driven arrays of Rydberg atoms in a tweezer-ladder geometry. The observation of gauge-invariant confinement dynamics is demonstrated to be in reach of current experimental techniques.

A concept for a staggered array undulator that can be constructed using bulk high-temperature superconductors and magnetized with pulsed field magnetization.

The many-body effects arising when coupling whispering gallery electronic (cavity) modes to a double-dot system are investigated. Conventional Kondo effects, where the dots hybridize with their leads, compete with a cavity-mediated dot-dot hybridization, engendering an exotic shuttling of Kondo screening between the leads and the formation of a Kondo-cat state.

Stochastic thermodynamics has unveiled several universal trade-off relations, but they do not have to be restricted to mesoscopic systems. The geometric structure of the thermodynamic forces in hydrodynamics reveals the similarity between stochastic thermodynamics and hydrodynamics and helps generalize the housekeeping–excess decomposition of entropy production and derive an inequality that resembles the thermodynamic uncertainty relations.

In low-disorder samples, bulk quasiparticles of the $\nu$ = 1 integer quantum Hall state are either randomly localized or ordered on a Wigner lattice. It is found that thermal activation energy has a dramatic behavior with the quasiparticle density, exhibiting conspicuous local minima at the crossover from the randomly localized phase to the Wigner solid.

Dislocations are explored as possible components of solid-state quantum devices. Their strain induces the creation of self-assembled arrays of defect-based qubits.

Many-body localization is studied in a model where the interaction seems to enhance the localization rather than reduce it. A mean-field theory is proposed to provide an accurate and intuitive understanding of the mechanism behind the enhancement.

The superfluid stiffness and the Josephson quantum capacitance of chiral-symmetric superconducting Dirac semimetals are shown to become quantized in nonuniversal units due to nontrivial topology. The topological constraint imposed on the total superfluid stiffness further leads to the here-termed quantum admittance effect, that is, the universal topological quantization of the admittance modulus when the system is subject to an ac perturbation with a frequency tuned at the absorption edge.

Can the strengths of the two leading magnetic confinement concepts, tokamaks and stellarators, be merged into one single flexible device? As a possible answer to this question, we propose a first-of-its kind optimized stellarator-tokamak hybrid. This hybrid requires only a single type of stellarator coil in addition to the tokamak coils; it has sufficient particle confinement, and it reduces the needed plasma current, which can be a driver for unwanted instabilities.

It is possible to create a bilayer system with broken spatial inversion symmetry by stacking two monolayers of 1$T$-type transition metal dichalcogenides with a 180${}^{\circ }$ twist, each originally possessing spatial inversion symmetry.

A study presents direct experimental probing of the electronic structures of boron oxide glass under compression up to 2.2-megabar pressures via inelastic x-ray scattering.

A study reveals that a neural network must have an exponentially large hidden layer relative to the input dimension to accurately learn the output of a teacher perceptron, emphasizing the significant size constraints necessary for perfect generalization in over-parametrized models.

Using pulse shape spectroscopy, we demonstrate long-lived electronic coherences in molecules, and we are able to disentangle the electronic and nuclear degrees of freedom by performing momentum resolved covariance measurements of the fragment ions as we vary the phase between pump and probe pulses. These results pave the way for measuring coupled electron-nuclear dynamics in molecules and understanding the role that electronic coherences play in fundamental photophysical and photochemical processes.

APS has selected 156 Outstanding Referees for 2024 who have demonstrated exceptional work in the assessment of manuscripts published in the Physical Review journals. A full list of the Outstanding Referees is available online.

Three journals are excited to announce a new article type, “Perspectives,” to provide forward-looking views of cutting-edge science that has recently emerged or is enjoying renewed activity.