Research articles

The quasiparticle the biexciton is expected to be an important component in the construction and application of quantum states in quantum information computing but is typically not stable under ambient conditions. Here, the authors use nanoplasmonics to achieve the generation of biexcitons at room temperature in perovskite nanoplatelets.

Magnetic skyrmions are topological objects that have been recently extensively studied for their particular characteristics and a view to be used in spintronics devices. The authors present a Small Angle Neutron Scattering study of the deformation of magnetic skyrmion lattice propelled by an electric current and find that the skyrmions experience frictional movement at the edges of their sample providing better understanding of the motion of skyrmions.

Revealing how to effectively produce nuclei remains one of the main motivations of recent nuclear reaction and nuclear transmutation studies of radioactive waste. The authors show the enhancement of proton rich isotope production using incomplete fusion mechanism on weakly bound nuclei using the incomplete fusion mechanism by the inverse kinematics technique, in which a radioactive beam of Palladium bombards a proton/deuteron target.

The superconducting proximity effect is the basis for topologically non trivial states in semiconducting nanowires, potentially useful for quantum information technologies. Here, the authors use integrated quantum dots as spectrometers to investigate the proximity effect, paving the way to systematic studies of subgap states.

Experimental verification of the Standard Model suffers from large errors when addressing spin-dependent Boson exchange between electrons and quarks. Here, optically trapped linear polyatomic molecules are proposed as probes of nuclear spin-dependent parity violation, exhibiting sensitivity which significantly exceeds the current state-of-the-art.

One of the core notions of quantum mechanics are cat states, pictorially described as a cat being simultaneously dead and alive. The authors describe an experimental realisation to generate a classical analogy to cat states using the orbital angular momentum degree of freedom of light and simulate the dynamical behaviours of the cat state in phase space.

Secure transfer of quantum information is of importance for the development of quantum technology such as quantum communication and storage. Here, the authors use carbon nuclear spins coupled to a nitrogen vacancy center to achieve reliable quantum state transfer of photon polarization.

The Casimir torque, a quantum effect caused by the vacuum and thermal fluctuations of the electromagnetic field, is a phenomenon that can cause friction, but is also a manifestation of the optical angular momentum of light. This work describes the transfer of angular momentum between spinning nanoparticles enabled by the Casimir torque and provides calculations for the rotational dynamics of the system.

Thunderstorms are thought to produce two types of high-energy emissions, terrestrial gamma-ray flashes and gamma-ray glows however due to the difficulty in their observation the exact relation between the two is still not well-understood. Here, the authors report the simultaneous detection of a gamma-ray glow and a downward terrestrial gamma-ray flash suggesting the origin of the two phenomena are related.

The anticipated role of skyrmions as information carriers in spintronic devices has, so far, been hampered by difficulties in controlling their motion. Here, the authors use micromagnetic simulations to investigate the temperature-dependent motion of skyrmions, revealing that their magnetic texture reacts on two different time scales.

Nuclear magnetic resonance is a technique ubiquitous in a diverse range of scientific and clinical fields. However, it can be sensitive to small deviations in the driving magnetic fields, which can easily disrupt measurement accuracy. Here, the authors develop a hybrid-state free precession approach which demonstrates greater robustness against deviations in the magnetic fields and exhibits an improved signal-to-noise ratio.

The hard disk model is generally applied to study melting in two dimensional colloidal solids, which for idealized 2D systems proceeds through a solid to hexatic - hexatic to fluid process, but impurities perturb the hexatic phase for real systems. The paper reports Monte Carlo and molecular dynamics simulations of a 2D system of polydisperse hard disks, finding that increasing polydispersity decreases stability of hexatic phase, and that even for polydisperse systems there are re-entrant transitions at high density, which is not observed for 3D systems.

The complex nature of polycrystalline materials mean that characteristics such as their electronic band structure can be more challenging to interpret than their single crystal counterparts. Here, the authors present a framework based on angle-resolved photoemission spectroscopy to reveal the band dispersions for azimuthally disordered transition metal dichalcogenide polycrystalline monolayers.

Graphene is expected to be of particular use for Hall sensors but aspects of its electronic band structure and transport properties still require careful examination. Here, the authors analyse the performance of graphene sensors near the charge neutrality point and demonstrate the required trade-offs required to maximise the performance of a graphene-based Hall sensor.

The study of electron dynamics in relativistic laser fields is a subject of major interest within the strong field physics community and has inspired several key applications aimed at accelerating charged particles. The authors present a theoretical study, and propose an experimental design, that address the interaction of electrons with intense lasers in the transition regime from classical to quantum and show that stochastic processes in the quantum regime allow electrons to be transmitted/reflected across/by the laser in the parameter region prohibited by classical dynamics.

Exceptional points are singularities in the parameter space of a system where, under certain conditions, gain and loss can coalesce and give rise to exotic behaviour. The authors report on the dynamical encircling of exceptional points in a waveguide system having more than two states, increasing our understanding of the chiral phenomena occurring in non-Hermitian systems.

BaFe₂Se₃ is a ladder-compound that exhibits superconductivity under pressure. Using a density matrix renormalization group calculation to compare results with resonant inelastic X-ray scattering measurements, the authors conclude that this material is realized in an orbital-selective Mott phase.

Ion production and acceleration is ubiquitous in astrophysical objects but many questions still remain on the mechanisms at play and while laboratory plasmas provide an “accessible” regime, non-thermal ion acceleration has not been observed in the laboratory before the advent of high-power lasers. The authors collide two relativistic plasma flows and observe large energy difference of the protons coming out of the interaction region with or without an external magnetic field, qualitatively corroborating their 1D and 2D particle-in-cell simulations.

The technological importance of silicon is unquestionable; however the indirect bandgap of this semiconductor results in low excitation efficiency in the far field region of the electromagnetic spectrum. Here, the authors adopt optical near field excitation to improve the efficiency of Si, also paving the way for photodector applications based on other indirect band gap materials.

Many problems in physics do not have an exact solution method, so their resolution has been sometimes possible only by guessing test functions. The authors apply Deep Reinforcement Learning (DRL) to control coherent transport of quantum states in arrays of quantum dots and demonstrate that DRL can solve the control problem in the absence of a known analytical solution even under disturbance conditions.