Volume 21 Issue 7, July 2022

Automated experiments can accelerate research and development. ‘Flexible automation’ enables the cost- and time-effective design, construction and reconfiguration of automated experiments. Flexible automation is empowering researchers to deploy new science and technology faster than ever before.

Hui Deng, professor at the University of Michigan, talks to Nature Materials about the evolution of research in polariton physics over recent years and discusses the role of emerging materials in promoting a scenery full of challenges and possibilities.

Sub-100-mV switching at the nanosecond timescale is achieved in ferroelectric devices by approaching bulk-like perfection in prototypical BaTiO₃ thin films.

Ultrathin CrSBr, a two-dimensional magnet, has been shown to exhibit very rich magnetic behaviours, from an unexpected magnetic order to optical emissions coupled to its magnetic state. This material has great potential for use in ultra-compact spintronics devices.

A hydroxide exchange membrane fuel cell consisting of a nickel-based anode and a cobalt–manganese–oxide cathode is shown to achieve a power density of 488 mW cm^–2 at 95 °C.

Excitonic states with hybrid dimensionality in layered silicon diphosphide exhibit interesting features such as linearly dichroic photoluminescence and unusually strong exciton–phonon coupling.

Giant exciton–polaritons come to the scene from a thin Cu₂O crystal sandwiched by a microcavity. Their anticipated strong interactions may facilitate the development of a promising Rydberg solid-state platform for quantum technologies.

Dynamic recrystallization helps to refine grain structures in metals and tune their properties. Confining recrystallization within prior nanoscale twinning provides a path for reaching exceptional grain refinement.

High-quality wafer-scale single-crystal monolayer graphene is achieved on sapphire substrate, by epitaxially growing graphene at the Cu(111)/sapphire interface and then detaching Cu film via immersion in liquid nitrogen and rapid heating.

The authors use scanning tunnelling microscopy and spectroscopy to visualize the electronic structure of mirror twin boundaries, revealing a Tomonaga–Luttinger liquid.

A ferromagnetic transition in CrSBr is attributed to ordering of magnetic defects, and can be electrostatically manipulated.

The realization of large-scale exciton–polariton platforms operating at room temperature and exhibiting long-lived, strongly interacting excitons has been elusive. Here, the authors demonstrate a room-temperature perovskite-based polaritonic platform with a polariton lattice size of up to 10 × 10.

Cu₂O is a promising platform to host Rydberg exciton–polaritons, where excitons strongly couple to cavity photons, however their realization has been elusive. Here, the authors report Rydberg exciton–polaritons with principal quantum numbers up to n = 6.

Distinct electronic and optical properties emerge from quantum confinement in low-dimensional materials. Here, combining optical characterization and ab initio calculations, the authors report an unconventional excitonic state and bound phonon sideband in layered silicon diphosphide.

Thin films of BaTiO₃ do not possess the same small switching fields and energies as the single-crystal form, hindering applications. Here, thin films are synthesized that enable switching for voltages <100 mV and fields <10 kV cm^–1, and a pathway to subnanosecond switching is presented.

Extreme mechanical deformation processes can lead to nanograins in many metals, but the underlying mechanism remains unclear. Nanotwinning-assisted dynamic recrystallization is shown to facilitate grain refinement to the nanoscale at high strains and strain rates.

Intercalation-type metal oxides are promising anodes for Li-ion batteries but suffer from low energy and power density together with cycling instability. A nanostructured rock-salt Nb₂O₅ formed via amorphous-to-crystalline transformation during cycling with Li⁺ is shown to exhibit enhanced performance.

Hydroxide exchange membrane fuel cells are promising as an energy conversion technology, but require platinum group metal electrocatalysts for their application. A Ni-based hydrogen oxidation reaction catalyst is now shown to exhibit unprecedented electrochemical performance.

Wiring photosynthetic biomachineries to electrodes is promising for sustainable bio-electricity and fuel generation, but designing such interfaces is challenging. Aerosol jet printing is now used to generate hierarchical pillar array electrodes using indium tin oxide nanoparticles for high-performance semi-artificial photosynthesis.

The performance of organic optoelectronic and energy-harvesting devices is largely dictated by molecular orientation and resultant permanent dipole moment. Here, the authors demonstrate a strategy to actively control dipole direction in organic glassy films.

Here the authors fabricate a fibre-coupled electrode ‘fibertrode’ that integrates light emission sites and platinum microelectrodes on tapered optical fibre neural implants, for combined stimulation and recording of neural activity over small brain volumes in vivo with reduced photoelectric artefacts.