Articles

Spontaneous parametric down-conversion, the standard technique for generating entangled photons, is limited by low pair extraction efficiencies at near-unity fidelity. The authors show quantum dots in nanowires efficiently emit an oscillating state with near-unity entanglement fidelity and propose a time-resolved quantum key distribution protocol.

Formulating a general nonequilibrium thermodynamics of quantum coherence and identifying conditions for it to affect work extraction has remained elusive. The authors develop derive generalized fluctuation relations and a maximum-work theorem that fully account for quantum coherence at all times and analyse a driven qubit as a benchmark system.

Maxwell’s demon refers to extracting a resource through measurement in a system, which for a quantum system can be done in a completely energy-conserving way. The authors present such a Maxwell’s demon method of subtracting bosonic energy of excited qubits for Janes-Cummings interactions to generate an out-of-equilibrium state.

Exploring the impact of higher-order interactions in swarmalator systems, the authors analyze a model with pairwise and higher-order interactions, revealing four collective states. They find that even with predominantly repulsive pairwise interactions, elevated higher-order interactions sustain correlation among the swarmalators and minute fractions of higher-order interactions induce abrupt transitions between states.

Lattice gauge theory, a subset of gauge theory, has been successfully applied to a range of quantum systems allowing for the investigation of localised phenomena within these systems. Here, the authors consider a non-Hermitian lattice model observing a quantum disentangled liquid state that exists in both the localised and delocalised phases.

Active matter is a non-equilibrium system exhibiting collective behaviour and can be used to describe a wide range of biological phenomena from groups of cells to flocks of birds. Here, the authors develop a minimal model for studying the collective behaviours of polar and disordered active materials.

While it is renown that the COVID-19 pandemic affected the population mobility, little attention has been given to modeling the structural patterns of park visitations, and how these patterns have changed. The authors perform such analysis via gravity model as well as network structure analysis, and link the recreational propensity to socio-economical status of the population.

Characterizing quantum phases realized in simulation can be difficult, such as the re-entrant gapless phase of the Kitaev model induced by a magnetic field. Employing a quantum-classical hybrid approach that involves mining projective snapshots with interpretable classical machine learning, the authors uncovered Friedel oscillations of a spinon Fermi surface, providing support for a gapless quantum spin liquid.

The mechanisms underlying the chemo-mechanic coupling of motor proteins is described by a set of force-velocity relations, yet their form is controversial in different species. The authors resort to Extreme-value analysis to study the motion of kinesin and dynein along microtubules determining the convexity of the governing relations for each motor.

In the design optimization of resonance frequencies and Q-factor of nanomechanical resonators, the influence of geometric design on the nonlinear dynamics has been rarely investigated. Here, the authors tune the stress field via soft-clamping, simultaneously increasing both the Q-factor and the onset of nonlinearity of a Si3N4 string resonator.

Einstein relations in non-equilibrium active matter systems break upon increase of fluctuations and changes in the system’s dissipative properties. By observing the tapping collisions of a tracer in a bath of vibrationally excited active granular particles, the authors propose a generalized active Einstein relation accounting for memory effects.

Tunable optical frequency combs are a flexible solution for applications in optics, but they are typically limited in reconfigurability or simplicity of the We agree to use the draft summary by the editor. setups. The authors present a frequency comb platform exploiting electrooptic modulation and nonlinear AlGaAs-on-insulator waveguide, ensuring reconfigurability and fast-switched repetition rates.

The Weyl semimetal represents a distinctive topological state of matter, yet understanding its behaviour in thin films remains challenging, despite its significance for device applications. The authors reveal the layer number dependence of the band topology and transport properties in atomically thin films of a ferromagnetic Weyl semimetal, Co shandite.

Vessel compression is reported as a cause of tumour tissue hypoxia, in turn related to reduced treatment efficacy and increased metastases. The authors investigate computationally how vessel compression affects blood flow in microvascular networks, detecting a reduced haematocrit value upon compression of the vessels and an increased haematocrit heterogeneity, postulating a causal relationship with the presence of tumour hypoxia.

Sedimentation is the settling under the action of gravity of particles suspended in a viscous fluid, a process that is influenced by many physical effects. Here the authors investigate the sedimentation of an achiral particle, a rigid U-shaped disk, in a regime where inertia is negligible and find evidence of chiral trajectories whose handedness is determined by the disk’s initial orientation rather than its shape.

Reservoir computing uses networks of interacting components to provide a flexible framework for decision-making, control, and signal processing, but the implementation is complicated by inherent parameter variabilities and uncertainties. The authors design a reservoir of FitzHugh-Nagumo oscillators exhibiting critical behavior and robustness across a wide range of resistive coupling strengths.

Editors Summary: Amorphous photonic structures offer a unique platform for studying unique optical transport phenomena in random media. The authors examine both experimentally and theoretically TE (in-plane) polarized near-infrared light in amorphous structures, demonstrating isotropic and asymmetric bandgaps, Anderson-like localized states at the midgap, and readily available practical waveguide structures.

The newly-synthesised α-RuI₃ has a much-debated ground state. Here, the authors demonstrate, using angle-resolved photoemission spectroscopy, that RuI₃ is a moderately correlated metal with an electronic band structure not having any in-plane symmetry, introducing the concept of pseudochirality to describe a similar band structure.

When an energetic charged particle or photon is incident on a material, matter-antimatter pairs, such as electron-positron pairs, can be created. Here, the authors successfully generate charge-neutral GeV electron-positron beams using a multi-petawatt laser via pair production from the bremsstrahlung gamma rays.

The use of nitrogen vacancy (NV) centers in diamond is a powerful approach for quantum sensing and can enhance the sensitivity of other techniques such as nuclear magnetic resonance (NMR). Here, the authors present a dynamic nuclear polarization technique, which enhances the efficiency of polarisation transfer from the NV centre at volumes suitable for NMR without being disrupted by other defects within the diamond.