Research articles

A combination of microscopy and spectroscopy techniques are used to directly observe a ferroelectric field effect and screening by oxygen vacancies at the BiFeO₃/La_xSr_1−xMnO₃ interface.

Malignant cells in tumours invade surrounding tissues. Single-cell-resolution measurements of the migration—through micropillar arrays—of a cell population following the epithelial-to-mesenchymal transition show intriguing emergent dynamics.

Recent work has proposed that both protein tethering to the extracellular matrix and matrix porosity can regulate stem cell differentiation. It is now shown that differentiation is driven by matrix stiffness independently of tethering and porosity.

The spin Hall effect plays a central role in generating and manipulating spin currents, but its magnitude is ultimately fixed by spin–orbit coupling effects. It is now shown that the spin-Hall-effect angle can be tuned electrically in GaAs.

Non-uniform metal deposition and dendrite formation on negative electrodes during repeated cycling are major hurdles to commercialization of batteries. Electrodeposited lithium in liquid electrolytes reinforced with halogenated salt blends has now been used for lithium cells, and exhibits stable long-term cycling.

Photocatalytic efficiency can be limited by slow transfer of photoexcited holes and high charge recombination rates. Using a hydroxyl anion–radical redox couple leads to enhanced photocatalytic H₂ generation on Ni-decorated CdS nanorods.

The temporal dynamics of phase transitions in strongly correlated states of matter are often dictated by the interplay between structural and electronic degrees of freedom. These are now probed in a perovskite manganite using an X-ray free-electron laser, and found to be well described by a single order parameter.

Although the Ruddlesden–Popper series of compounds offer a range of appealing properties, their fabrication in thin-film form has been challenging. Using molecular beam epitaxy, layered oxide films of this family are synthesized, and shown to undergo a dynamical rearrangement during the growth process.

A polymer–peptide surface coating that non-covalently binds the natural lubricant hyaluronic acid (HA) is shown to enhance the lubricity of tissue surfaces and to retain HA in articular joints and on ocular tissue surfaces in vivo.

Synthetic polymers functionalized with mussel-inspired catechols have been shown to exhibit self-healing and adhesive properties, mediated by metal chelation, that are much needed in biomedical and environmental applications. Now, a metal-free approach to complete polymer self-healing underwater mediated by extensive hydrogen bonding in catechol-functionalized polyacrylates is reported.

The dynamic control of thermal emission via the control of emissivity through intersubband absorption in n-type quantum wells, at a speed four orders of magnitude faster than is currently possible, is now demonstrated.

The electronic and structural components of charge density waves occurring in layered transition metal dichalcogenides are known to be interdependent, yet have only been probed in separate measurements. Now, a broadband terahertz spectroscopy approach that monitors the evolution of these two order parameters simultaneously is demonstrated.

A porous organic-cage molecule is shown to exhibit unprecedented performance for the separation of rare gases, with selectivity arising from a precise size match between the rare gas and the organic-cage cavity.

Many catalytic reactions exhibit oscillatory behaviour but these oscillations are not well understood for catalysts consisting of supported nanoparticles. The study of oscillatory CO oxidation catalysed by Pt nanoparticles now reveals that periodic changes in the CO oxidation are synchronous with a periodic refacetting of the Pt nanoparticles.

Palladium is of practical use as a hydrogen-storage metal and an effective catalyst for reactions related to hydrogen in a variety of industrial processes. Enhanced capacity and speed of hydrogen storage is now reported in Pd nanocrystals covered with a metal–organic framework.

The excitations that determine the low-temperature properties of ferromagnetic materials are called spin waves. Using a combination of inelastic electron tunnelling spectroscopy and numerical simulations, the spin waves occurring in a one-dimensional chain of iron atoms deposited on Cu₂N are now imaged, and their dynamics examined.

Until now, it has not been possible to switch chirality in plasmonic nanostructures at will and repeatedly. Now, thanks to DNA-regulated conformational changes, reconfigurable 3D plasmonic metamolecules with switchable chirality have been created.

The performance of solar cells based on organic–inorganic perovskites strongly depends on the device architecture and processing conditions. It is now shown that solvent engineering enables the deposition of very dense perovskite layers on mesoporous titania, leading to photovoltaic devices with a high light-conversion efficiency and no hysteresis.

Three-dimensional Dirac semimetals such as Cd₃As₂ are attracting attention because their electronic structure can be considered to be the three-dimensional analogue of graphene’s. Low-temperature scanning tunnelling measurements of the 112 cleavage plane of Cd₃As₂ now reveal its electronic structure down to atomic length scales, as well as its Landau spectrum and quasiparticle interference pattern.

The combination of photonic and spintronic devices offers significant promise for optoelectronic applications. In analogy to a photovoltaic cell, an optoelectronic device that spatially separates electrons with opposite spin orientations on absorption of circularly polarized light is now demonstrated.