Oxide-based solid-state protonic electrochemical transistors that have symmetric operation and are compatible with CMOS technology can be used to create crossbar arrays for deep learning applications.

A millimetre-wave dual-rail resonator that is incorporated into a suspended lithium niobate resonator can provide efficient electromechanical transduction in the sub-terahertz regime.

The Curie temperature of Fe_5+xGeTe₂ thin films can be modulated from 260 to 380 K via iron doping, allowing the two-dimensional material to be used to create planar spiral inductors and low-pass Butterworth filters.

Magnetic meta-atoms made from lanthanum-doped barium hexaferrite can be used to create self-biased non-reciprocal metasurfaces capable of unidirectional transmission, non-reciprocal beam steering, non-reciprocal beam focusing and non-reciprocal holography.

An organogel that is based on poly(vinyl alcohol)–sodium borate and contains a percolating conductive network of silver particles and liquid metal microdroplets exhibits spontaneous mechanical and electrical self-healing, as well as an electrical conductivity of 7 × 10⁴ S m⁻¹.

Magnetic hysteresis in multiferroic heterostructures formed from the two-dimensional magnetic insulator chromium germanium telluride and a thin ferroelectric polymer can be electrically controlled with voltages of around 5 V.

Micro-light-emitting diodes — microLEDs — could be used to create the next generation of displays, for use in smartwatches and augmented reality devices, if various fabrication issues can be addressed.

Micro-light-emitting-diode display applications are growing quickly as technology companies begin to use them in a range of products. Key to the development of these applications was the miniaturization of gallium nitride light-emitting diodes. Hongxing Jiang and Jingyu Lin recount how this was achieved.