The authors present several methods for heading error suppression in all-optical alkali-vapor magnetometers in geomagnetic field ranges. These improvements could result in more precise measurements of Earth’s magnetic field and the development of compact and miniaturized sensors.

The authors study the effect of Doppler broadening on a quantum heat engine based on electromagnetically induced transparency which has recently been suggested and demonstrated with ultracold atoms. They show that “warm” atoms can still be used as a coherent quantum working medium, which suggests the possibility of a simpler and more convenient implementation than previous realizations with ultracold atoms.

The authors theoretically propose and experimentally demonstrate a scheme for generating time-bin entanglement with a quantum memory based on an ensemble of room-temperature atoms. The results are interesting for the manipulation of quantum information in quantum networks and may serve as an element in future quantum repeaters and quantum computers.

The authors present a composably secure protocol allowing $n$ parties to test an entanglement generation resource controlled by a possibly dishonest party. The test requires only local quantum operations and authenticated classical communication once a state is shared among them. The composability ensures that the protocol can be used multiple times in a row or as a subroutine in any bigger protocol without threatening the overall security.

The authors theoretically study the polariton dynamics in single- and two-body Jaynes-Cummings systems and identify mechanisms that allow interchange of polariton branches. The results provide insights into controlling the Mott insulator to superfluid transition.

The authors experimentally prepare and investigate the properties of a strongly interacting imbalanced mixture of bosonic 41K impurities immersed in a Fermi sea of ultracold 6Li atoms. Two configurations have been explored: a thermal regime described by the Fermi polaron picture and a partially Bose-Einstein-condensed regime described by coexisting Fermi and Bose polarons.

The authors study experimentally accessible lower bounds on entanglement measures for quantum many-body systems based on entropic uncertainty relations. Rather than requiring the full reconstruction of the quantum state, the bound derived here requires measuring joint probability distributions in only two different measurement settings per subsystem.

The authors present the construction of cellular automaton models corresponding to free quantum field theories for both fermions and bosons, and demonstrate that for wavelengths long compared to the lattice spacing one recovers standard Dirac and Maxwell field theories. Correspondences such as this offer a new way of thinking about quantum field theories, and potentially a new way of simulating them on quantum computers.

The authors develop and implement experimentally a procedure for quantum-state reconstruction of the complete rotational wave function of a simple molecule. The reconstruction procedure can be adopted without any information on the field-matter interaction to create the rotational wave packet.

The authors propose a nonreciprocal phonon laser in a spinning microwave magnomechanical system, consisting of a spinning microwave resonator coupled to an yttrium-iron-garnet sphere. These results could potentially be useful for manipulating cavity magnomechanical systems through the Fizeau light-dragging effect.

At the beginning of 2021, eight Physical Review journals began publishing Letters which are intended for the accelerated publication of important new results targeted to the specific readership of each journal.

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.

APS Editor in Chief, Michael Thoennessen, discusses a new opportunity for communicating authors to include their pronouns together with their contact email in order to promote a more respectful, inclusive, and equitable environment.

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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