The authors offer an overview of progress and a future perspective of large-scale optical quantum entanglement. They cover a broad range of topics from the basics of continuous-variable optical quantum entanglement and a multiplexing methodology for the generation of large-scale quantum entanglement to future approaches toward practical usages of large-scale optical quantum entanglement. The content includes both pedagogical content and the search for future directions beyond the current frontier.

Physical Review A is excited to offer better visibility and a tailored abstract for our popular Letter articles.

Alongside its companion in $Physical$ $Review$ $Letters$, this paper reports on the similarities and differences between the information-theoretic and relativistic notions of causality, bringing them together under a single framework. This sheds light on a long-standing debate on whether experimentally realizable processes are truly indefinite causal ordered processes.

The authors study the effects of the interaction of a strong laser field with free electrons produced by strong-field ionization on the quantum state of the field. They show that under experimentally realistic conditions the interaction can strongly affect the quantum state of the field by squeezing and displacing the coherent state of the free field, which can result in the formation of nonclassical and non-Gaussian field states.

The authors demonstrate that one-dimensional Bose-Bose mixtures support multipole quantum droplets. These states feature different atomic density distributions in the two species and cannot be found in the reduced single-component model.

The authors study Thouless pumps, i.e., adiabatic topological transport, in an interacting spin chain described by the dimerized $XXZ$ Hamiltonian. They show that a new adiabatic path for a Thouless pump is possible for an interacting spin chain in which interactions can induce a spontaneous antiferromagnetic order.

The authors develop an approach to directly control the phase of an electron’s sub-cycle motion in an intense laser field by tuning an additional low-frequency electric field. A key formula connecting the low-frequency electric field with the harmonic frequency shift is found, suggesting in situ applications including continuously tuning XUV waves and sampling terahertz pulses.

The authors blueprint a superconducting “Bose condenser,” a device where nonequilibrium Bose-Einstein condensation of photons into single or multiple modes can be controlled on demand, through the coupling to artificial quantum baths.

The traditional approach to understanding an interaction between physical systems involves explaining the experimental statistics with some model of interaction. The author here proposes an alternative approach where the interaction is explained via experimental statistics. By assuming systems behave according to quantum theory, their method uses Bell inequalities to infer entangling quantum interactions among an arbitrary number of quantum systems from statistical data.

The authors experimentally studied the dissociative recombination of electronically and vibrationally relaxed ArH^+ in its lowest rotational levels, using an electron-ion merged-beams setup at the Cryogenic Storage Ring. They find that the unusually slow reaction rate at low collision energies is driven by nonadiabatic interactions where dissociation occurs on the loosely bound electronic ground-state ArH.

Finding ferromagnetic ground states of the Hubbard model, which usually features antiferromagnetic spin correlations, has been an outstanding challenge since Nagaoka’s celebrated (but experimentally unrealistic) proposal in 1966. Here, the authors show how such elusive itinerant ferromagnetism can be enhanced by kinetic frustration or occupation-dependent hoppings and demonstrate the relevance of these mechanisms to recent optical-lattice experiments.

In this paper, the authors use numerical solutions to the time-dependent Schrödinger equation, perturbation theory, as well as analytic expressions to investigate nondipole effects in the RABBIT technique, studying a helium atom subject to a linearly polarized XUV and a weak IR field. By scanning the time delay between the two fields, they observe modulations in sidebands both for the angular-integrated photoelectron yield and for the forward-backward asymmetry in photoelectron distribution along the light-propagation direction.

The authors demonstrate how the interplay between intrachain and interchain interactions in a dipolar spin chain results in three distinct relaxation regimes: ergodic, characterized by rapid relaxation towards equilibrium; metastable, where the state is quasi-localized; and partially relaxed, exhibiting both partial ergodic and quasi-localized behaviors simultaneously.

The authors present quantum scattering calculations on magnetic Feshbach resonances (MFRs) in ultracold atom-molecule collisions. The calculations predict a wealth of experimentally detectable MFRs in Rb-SrF collisions and uncover new MFRs due to the intramolecular spin-rotation interaction. These results open up the possibility of unbiased theoretical simulations on MFRs in ultracold atom-molecule collisions with realistic interactions.

The authors explore candidates for a next-generation search for the electron electric dipole moment (eEDM) by experimentally measuring the vibrational loss channels in three Sr-containing nonlinear molecules. They conclude that SrNH${}_2$ is the optimal choice for a future laser-cooled molecule-based eEDM experiment.

The policy requires authors to explain where research data can be found starting Sept. 4.

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

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.

We are very pleased to offer the readers of Physical Review a new, carefully curated collection of articles from the vibrant field of laser-plasma particle acceleration. Some of the articles have already been published, and others will be forthcoming. This Collection is the latest in the journal’s series of Special Collections on current or emerging fields and topics.

Physicists working in optics, atomic and molecular physics, and quantum information reflect on landmark papers and how they influence research today.

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