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

We are pleased to announce that Sarma Kancharla will assume the position of Chief Editor at PRB, effective April 29, 2024.

Cavity quantum electrodynamics (QED) studies the interaction between light and matter at the single quantum level and has played a central role in quantum science and technology. Combining the idea of cavity QED with moiré materials, the authors develop here a theory of cavity moiré materials, i.e., moiré materials confined in a cavity. These results indicate that the cavity confinement enables one to control magnetic frustration of moiré materials and might allow the realization of various exotic phases, such as the quantum spin liquid.

Anderson localization is a fundamental phenomenon in condensed matter physics, with strong connections with many-body localization and quantum chaos. A crucial theoretical problem is that its behavior on the Bethe lattice, an infinite loop-less tree, differs dramatically from realistic models in finite dimensions. To amend the theory, the authors study here tree-like lattices with one loop of arbitrary length. The outcome opens the way to the computation of the critical exponents and explains some puzzling finite-size effects observed in numerical simulations.

The chiral Aubry-André model is introduced as an atomic chain with staggered hoppings and a superimposed hopping modulation, revealing a unique interplay of one-dimensional and two-dimensional topological properties. Here, the authors describe the model’s phases and the coexistence of a 2D Chern number and a 1D winding number, combining features of the integer and half-integer quantum Hall effect with SSH-type 1D protected edge modes, motivating the engineering of complex topological insulators using the physics of quasicrystallinity.

Room-temperature quantum computing and solid-state quantum simulations have been long-standing goals in the field of quantum information science. Magnon Bose-Einstein condensation at room temperature may provide a key advance towards these objectives. Normally, the magnon Bose-Einstein condensation is driven by microwave pumping and detected by light. Here, the authors propose a method to create stable magnon condensate using lasers in a magneto-optical cavity, opening new avenues for all-optical control in quantum magnonics.

Ultrafast transverse magneto-optical Kerr effect (T-MOKE) spectroscopy in the extreme ultraviolet provides element-specific insights into magnetization dynamics. However, the relationship between T-MOKE magnetic asymmetry and sample magnetization can be complex, even in the absence of nonequilibrium magnetization dynamics. Here, the authors present static and time-resolved data, together with wave propagation simulations, for a prototypical magnetic heterostructure that shows significant deviations from linearity, including increasing asymmetry despite decreasing magnetization. They also propose sample structures and experimental geometries in which a linear T-MOKE response remains valid.

Nuclear magnetic resonance is typically performed at high magnetic fields, where heteronuclei are weakly coupled and resonate at their own frequences. This paper presents how hyperpolarization enables detection in the intermediate and strong-coupling regimes by using ultrasensitive SQUID setups. The authors also analytically derived product operators for this system (${}^{13}$C-labeled pyruvate) at arbitrary magnetic field. This confirms that spin precession does not occur at zero field, but rather that spins oscillate along an axis, demonstrating the importance of detection direction.

Transmon ionization (TI) is detrimental to qubit coherence and manipulation. This study explores how TI, triggered by strong microwave pulses, affects microwave single-photon detectors (SPDs) based on a 3D multimode cavity coupled to a transmon qubit. Experimental and numerical investigations reveal that at a critical pump power transmon population suddenly increases, indicating a quantum-to- classical transition. The authors also outline the challenges and potential solutions for increasing the quantum efficiency of SPDs, being crucial for advancing quantum communication and sensing technologies.

The authors present here a new paradigm for hybrid light-matter particles based on Landau’s quasiparticle concept. Specifically, they show that exciton polaritons form novel polaronlike quasiparticles due to interactions with the dark excitonic medium that is typically present in a semiconductor microcavity. This theory provides a new mechanism for the loss of light-matter coupling commonly observed in experiments, and it explains recent puzzling measurements on polariton interactions in atomically thin semiconductors, thus opening a pathway for engineering strong interactions in light-matter systems.

Vacancies in semiconducting 2D transition metal dichalcogenides enable studies of quantum phenomena at the nanoscale, such as single photon emission or Jahn-Teller distortions. Here, the authors show that a scanning tunneling microscope can enable local creation of single vacancies as well as vacancy dimers in single-layer MoS${}_2$. Charging the vacancy through local gating leads to two distinct types of Jahn-Teller distortions, in quantitative agreement with $ab$ $initio$ calculations. Strong hybridization within vacancy dimers illustrates the potential for artificial defect lattices with tailored electronic band structures.

Here, the authors demonstrate that cavity quantum electrodynamical effects induce electrostatic interactions between low-energy matter excitations when these are off-resonantly coupled either directly to the cavity field or indirectly via resonant mediator modes. These findings expose the limitations of previous models that have used just one cavity mode in the electromagnetic description of the cavity. The results provide critical insights for designing nanophotonic structures leading to significant cavity-induced interactions, which could open new avenues for modifying material properties using vacuum fields.

The magnetic skyrmion lattice is a crystallization of spin-swirling particle-like objects composed of multiple helimagnetic modulation waves with the same helicity (sense of rotation). Despite the widespread observation of this spectacular structure, the experimental verification of the unified helicity has not yet been achieved. Using circularly polarized resonant x-ray diffraction, the authors study here the triangular skyrmion lattice in the chiral helimagnet EuPtSi and demonstrate that the helicity is indeed unified. This method has great potential for unraveling the chiral structures of emergent magnetic phases.

The warm dense matter regime is generally found in materials compressed to several times their densities on the Earth’s surface at temperatures hot enough to produce a conducting fluid, but not so hot that the cohesive binding is overwhelmed by the temperature. This region of phase space is notoriously difficult to constrain with theoretical models. Iron is the most stable element, and is relevant to astrophysics, planetary physics, and industry. The paper here describes experiments using giant kilojoule lasers to shock compress iron to warm dense matter conditions and then send acoustic waves through this compressed material. This method yields the first experimental measurements of sound speed and Grüneisen parameter in shocked iron in the terapascal range, and reveals an interesting dependence on density and melting for these physically important derivatives of the equation of state.

In the emerging field of orbitronics, the orbital Hall effect stands out as one of the most important transport phenomena of orbital angular momentum. Here, the authors present a highly efficient and accurate first-principles method to compute the orbital Hall effect by Wannier interpolation and point out the crucial role of the anomalous position for the gauge-covariant description. The work guides the ongoing experimental efforts on the quantitative measurement of orbital currents.

Generic many-body particle systems typically exhibit chaos and thermalization. Amidst this chaotic landscape there are special systems called integrable, for example, systems of noninteracting particles that are neither chaotic nor thermalizing. Integrable systems usually require a high degree of fine-tuning of the Hamiltonian that defines their dynamics. The authors find that these special systems act as natural geometric attractors of adiabatic flows that follow the directions of fastest relaxation of observables. They also found that near integrability observables exhibit universal slow relaxation in time, forming long-lived nonequilibrium states similar to turbulent cascades.

Physical Review B is proud to announce the creation of an Early Career Researcher Advisory Board (ECAB). The 18 inaugural members are listed on the PRB Editorial Team page. We thank them for agreeing to serve. They will act as a focus group and provide advice from their perspective on how PRB can best serve the needs of early career researchers and maintain its important role in condensed matter and materials physics going into the future. The new board members are based in 10 different countries. Stephen Nagler, PRB Lead Editor, will chair the board.

PRB Editorial Team page

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.