Articles in 2022

Transparent conductive oxides are wide bandgap conductors that combine weak optical absorption. Here, the authors report a two-dimensional electronic state on the surface of La-BaSnO₃ and study its properties using a combination of electronic structure measurements and DFT calculations.

The total reaction flux catalysed by immobilized enzymes depends on their spatial arrangement. The problem of optimizing the arrangement to maximize the reaction flux is analogous to a portfolio optimization problem, which is solved here to obtain the optimal strategy to position enzymes in a class of reaction-diffusion systems.

Multistability is the possibility of a dissipative quantum many-body system to have multiple steady states - it is intensely studied, but its existence remains controversial. The paper settles this by providing an exactly provable case, and also proves that boundary time crystals can exist in interacting lattice models, which was not known before.

Elucidating the different microscopic mechanisms approaching the glass transition is challenging, particularly when considering the evolution of a supercooled liquid. Here, using synchrotron-based methods, the authors report the evolution of the dynamics in supercooled metallic liquids and unpick the structural and kinetic contributions to the α-relaxation process near the glass transition.

In a bilayer semiconductor system, electron-hole excitations, of which the simplest are electron-hole pairs known as excitons, can form by the interaction of charge carriers across the layers to come in various guises depending on the number and type of the charge carriers involved. Here, the authors theoretically investigate the Wigner crystallization of charged interlayer excitons as a function of perpendicular magnetic field applied, discussing how this phase transition could be detected in photoluminescence experiments.

Quantum Random Number Generators (QRNG) are important components of cryptographic protocols including prepare-and-measure based quantum key distribution protocols. The authors demonstrate laboratory, as well as in-orbit operation of their QRNG, showing its use to implement a public randomness beacon.

Experiments indicate that the cuprates exhibit intertwined spin- and charge-stripe orders and have sizable electron-phonon interactions. Here, the authors use quantum Monte Carlo methods to investigate stripe orders in the Hubbard-Holstein model to shed light on the influence of electron-phonon coupling on static and fluctuating stripe order.

Low phase-noise THz wave generation is in high demand for applications such as wireless communications and radars. Here, the authors generate low-noise THz waves via photodetection of the carrier of a Kerr frequency comb, which is repetition-rate stabilized using a two-wavelength delayed self-heterodyne interferometer.

Positive lightning discharges are rare and not well understood. Here, the authors present observations from three positive discharges and demonstrate unexpected luminosity dips in the channel to ground, as well as transient coupling to a negative discharge nearby.

Spin torque nano-oscillators facilitate the control of magnetization dynamics without the need for an external magnetic field and are compatible with CMOS technologies. Here, the authors propose, using micromagnetic simulations, a device comprising of an elongated-skyrmion-based spin torque nano-oscillator, which can be controlled using a spatially uniform current. This elongated skyrmion can also serve as a magnonic waveguide.

Plasma created nanoparticles have become a valuable technological product in many fields, from solar cells to pharmaceutical applications. The authors use self-excited dust density waves to study the properties of an electron depleted plasma containing nanodust particles, and show that a variation of particle size and concentration has only minor effects on the ion generation and density.

Porous media that display a gradient in the structure of their networks are common in nature, but the understanding of the drainage patterns in such media is still limited. We propose a theoretical framework that allows to better quantify these patterns, and we validate it both with experiments in 3D printed models and with numerical simulations.

Organic solar cells, despite their high power conversion efficiencies, suffer from open circuit voltage losses making them less appealing in terms of applications. Here, the authors, supported with experimental data on small molecule photovoltaic cells, relate open circuit voltage to photovoltaic gap, charge-transfer state energy, and donor-acceptor interfacial morphology.

Anomalous-diffusion identifies the departure of diffusive dynamics from the traditional Brownian-motion and is a signature feature of a large number of complex soft-matter and biological systems. This article reports an analysis of an easy to implement method to decide on the type of an apparent anomaly, even in the presence of localisation errors.

Accurate understanding of the dynamics of correlated quantum many-body systems is of interest in many fields. Here the authors explain the exchange–correlation induced red-shift and incipient roton feature of the dynamic structure factor of the warm dense electron gas in terms of electronic pair alignment model.

Berry curvature is the key component underlying various band geometric characteristics of solid state systems. Here, the authors investigate second-order susceptibility using perturbation theories and time-dependent simulations showing that the transverse optical response in insulators is governed by an interband Berry curvature dipole.

Dissipative optical solitons can exhibit bound states with exciting molecule-like interactions. This work demonstrates the reconfigurable switching of soliton molecular complexes beyond diatomic molecules in an ultrafast laser system, which provides novel perspectives in understanding soliton interactions and triggers potential applications in ultrafast science.

The study of topological defects in matter is a topic of extensive interest, but it remains challenging when it concerns non-equilibrium active matter. The authors experimentally and computationally demonstrate that obstacles immersed in a two-dimensional active liquid crystal can pin a type of defects and slow down the dynamics of nearby defects.

The classical picture of cyclotron resonance fails to describe the interaction between large-amplitude plasma waves and low-energy particles. The authors identify anomalous resonance, or nonlinear modification of the classical resonant condition by strong wave field, by ultrafast spacecraft measurements that are consistent with test-particle simulations.

Light-matter interaction has been dominated by Born-Oppenheimer approximation for centuries. Here the authors proposed a light-matter interaction mechanism beyond this approximation, proposing stimulated phonon polariton-mediated light-matter interaction, showing further understanding and applications in the fields of optics/photonics and condensed-matter physics.