Articles in 2021

A 2D electron gas is known to form at the interface of some oxides. Here, 2D electron density is studied in the LaIn_1-xGa_xO₃/Ba_0.997La_0.003SnO₃ interface, revealing that increased alloying causes the migration of dislocations to the interface, destroying coherency and preventing 2D electron gas formation.

Hybrid organic-inorganic perovskites are known to display unique optical properties. Here, electronic transitions in 2D copper-based hybrid perovskites are studied experimentally and theoretically, revealing how ligand size can be used to tune electronic and optical behavior.

Oxygen species on a TiO2 surface exist in different redox states, which can be switched between by electron tunneling with an atomic force tip. Here, a fast experimental setup enables statistically significant tunneling rates to be determined, revealing changes in electronic structure.

Understanding the connection between qubit coherence and microscopic materials properties is vital for improving device performance. Here, the relaxation times of superconducting transmon qubits are found to be directly correlated with Nb film properties such as grain size and surface oxide composition.

Face masks are key for slowing the spread of COVID-19. Here, the microstructure of three common masks is determined by x-ray tomography, combined with image-based modelling of droplet permeability, revealing that N95 masks are best for droplet filtration.

Halide perovskites recently attracted wide attention for light emitting applications. Here, octahedral distortion in halide double perovskites Cs₂AgMCl₆, induced by the mixture of trivalent M-cations Bi³⁺, In³⁺, and Sb³⁺, gives rise to enhanced white light emissivity and longer photoluminescence lifetimes.

Understanding the mechanism of supercooling suppression by crystallization seeds is important for designing semiclathrate hydrates for latent heat storage materials. Here, we show that 10-30 nm cluster formation around silver nanoparticles promotes crystallization of supercooled aqueous solutions.

Microbiologically influenced corrosion is a major source of degradation of metals. Here, extracellular electron transfer is studied during pitting corrosion of stainless steel in the presence of an electroactive bacterium and a riboflavin electron shuttle, revealing bidirectional electron transfer.

The redistribution of water molecules when an ion passes through a nanopore is known to create complex patterns. Here, an analytical model accurately predicts the patterns when an ion passes through a graphene nanopore, and reveals the physical origins of the patterns.

There is growing interest in flexible electronic devices, though their soft nature can make them vulnerable to damage. Here, a liquid metal-elastomer composite is shown to self-heal, can be stretched 1200% with limited change in electrical resistance, and the conductive circuit can be reconfigured.

Topological boundary modes in mechanical systems have recently attracted great attention due to their unique protection features. Here, tunable corner localization of mechanical waves is numerically and experimentally demonstrated in a continuous elastic plate with hexagonally arranged bolts.

Understanding adhesion mechanisms for polymer composites is challenging due to the bonded interface being buried. Here, soft X-rays are used to probe the chemical and physical nature of the interface, revealing multiscale factors that influence the adhesion mechanism and bond strength.

The study of water at high pressure and temperature is essential for understanding planetary interiors but is hampered by the high reactivity of water at extreme conditions. Here, indirect X-ray laser heating of water in a diamond anvil cell is realized via a gold absorber, showing no evidence of reactivity.

Plant cells are elaborate three-dimensional polymer nano-constructs with complex chemistry. Here, multimodal scattering nearfield optical microscopy of poplar trees is used to establish in situ high-resolution mappings of the local dielectric functions and compositional distribution of lignin and cellulose in plant cell walls.

Theoretical treatments of electrocaloric effects, interesting for their potential use in refrigeration, are mostly case specific. Here, a perturbative approach provides a unified physical understanding of the normal and inverse electrocaloric response occurring in ferroelectrics and antiferroelectrics.

Thermal treatments are important for controlling the microstructure and mechanical properties of precipitation-hardened alloys. Here, an up-quenching process enhances clustering kinetics in an Al-Mg-Si alloy, attributed to retained high temperature vacancies assisting diffusion at low temperature.

Shape-shifting structures are important building blocks in the design of reconfigurable materials and devices with advanced functionalities. Here, versatile metamaterials with 3D-to-3D shape-shifting behavior upon thermal activation are fabricated by adapting a 3D printer to print on curved surfaces.

Surface acoustic waves are important in a wide range of applications such as telecommunication filters, sensors, and microfluidic devices. Here, patterning of a phononic metamaterial formed of annular hole resonators enables frequency control of the surface wave phase velocities.

Amphiboles are hydrous silicates occurring in many rock types in the continental crust and subduction zones. Here, in situ Raman spectroscopy of grunerite reveals temperature-activated electron-phonon excitations that provide an atomistic insight into the role of amphiboles in the anisotropic lithospheric conductivity.

Studying the bonding of organic molecules onto the surface of metal nanomaterials is important for understanding their plasmonic properties. Here, changes in the electron density of states at the metal-ligand interface of Ag nanoparticles are linked to variations in localized dipole moments and interface permittivity.