Volume 20 Issue 1, January 2026

Optical computing has been limited to vector–matrix multiplications, with matrix–matrix operations requiring wavelength- or time-division multiplexing, reducing energy efficiency and speed. Now, researchers have demonstrated a free-space optical approach that overcomes these limitations, enabling parallel matrix–matrix and tensor–matrix multiplications in a single optical operation.

A nanostencil lithography technique enables fabricating arrays of green-emitting OLEDs with pixels as small as 100 nm and an external quantum efficiency of 13.1%.

From super-resolution endoscopes to multi-photon microscopes, photonic technologies are being translated from laboratory innovations to tools for clinical diagnosis and biological inquiry.

This Review discusses recent advances in interlayer engineering for perovskite solar cells, highlighting promising materials and architectures that could improve the stability and efficiency of devices.

Performance of solid-state triplet fusion upconversion films is enhanced by surface plasmons, intensity threshold is reduced by a factor of 17 and external quantum efficiency is enhanced by a factor of 19. A white-emitting organic light-emitting diode featuring upconverted blue emission—rather than blue electroluminescence—is demonstrated, with a colour rendering index of up to 86.2.

Nanostencil etching and lithography enable the fabrication of green-emitting nanoscale organic light-emitting diode pixels with size as small as 100 nm, densities as high as 100,000 pixels per inch and average external quantum efficiency of 13.1% for green emission.

An engineered self-assembled monolayer improves perovskite crystallization, enabling perovskite–silicon tandem solar cells with a certified power conversion efficiency of 33.59%, 90% of which is maintained after 2,000 h of operation at ambient temperature.

Observation and control of spin-forbidden dark excitons is demonstrated in a hybrid heterostructure of WSe₂ monolayers and plasmonic nanocavities.

Engineering the perovskite–electrical contact interface with sodium heptafluorobutyrate reduces interfacial defects and improves charge transport in perovskite solar cells. Functionalized devices deliver a certified power conversion efficiency of 26.96%, which is fully retained after 1,200 h of continuous operation under 1-sun illumination.

Catalyst-free conversion of methane and carbon dioxide using light of various wavelengths under ambient conditions is reported.

Integrating a thin-film resistance thermometer above a high-Q SiN microresonator enables local temperature monitoring and active stabilization of its resonance wavelength. The emission wavelength of a distributed feedback laser locked to the microresonator fluctuates within 0.5 pm over a period of 50 h.

Researchers demonstrate phase-stable sub-cycle self-compressed light transients, as well as their sampling down to half of an optical cycle, and determine their waveform phase offset. They apply the transients to soft X-ray high-harmonic generation and attosecond X-ray absorption spectroscopy.

The quantum fusion of two independent 10-user networks is demonstrated based on multi-user entanglement swapping. Active temporal and wavelength multiplexing schemes are developed to merge the two networks into a larger network with 18 users in the quantum correlation layer.

High-power, tunable accelerator-based terahertz radiation is demonstrated. By electron-beam manipulation through laser heater beating, tunable capability from 7.8 to 30.8 THz, narrow spectral bandwidths (ranging from 7.7% to 14.7%) and pulse energies up to 385 μJ are obtained.

The researchers demonstrate parallel optical matrix–matrix multiplication, which enables fully parallel tensor processing through a single coherent light propagation. The approach provides a scalable, high-efficiency foundation for advancing next-generation optical computing.

Red, green and blue organic field-effect light-emitting transistors in which charge-carrier transport and light emission are spatially separated to improve exciton management and device efficiency are reported.

The additive molecule DHHB enables UV shielding, chemical passivation and strain regulation at the buried interface of perovskite solar cells. Small-area devices achieve a power conversion efficiency of 26.47%, 96% of which is maintained after 1,132 h of continuous operation.