Volume 19 Issue 5, May 2025

The experimental realization of a 3D cluster quantum state paves the way for information processing employing quantum error correction.

Local measurements of biological voltage production are key drivers of understanding in neurobiology and neurological and cardiac pathophysiology. Researchers have now shown that exciton–trion conversion in a two-dimensional semiconductor, MoS₂, can be used to optically image cardiomyocyte action-potentials in real-time.

A programmable quantum chip has been developed that generates, manipulates, and launches five-dimensional entangled photons into free-space channels, encoded as optical vortex modes, thus bridging the worlds of integrated and free-space quantum photonics.

This Review summarizes the recent progress in ultrahigh-bandwidth optical-fibre communications based on integrated optical frequency comb technologies, or integrated Kerr microcombs, highlighting the challenges and opportunities ahead.

By integrating a moiré photonic structure on-chip with advanced microelectromechanical system (MEMS) technology, an in situ twisted moiré photonic platform that can be tuned is realized, enabling nanometre-scale positioning of two optical nanostructures in either the near- or far-field coupling regime.

Combining on-chip photon-pair sources, two sets of linear integrated circuits for path entanglements and two path-to-orbital angular momentum converters, free-space-entangled orbital angular momentum photon pairs can be generated in high-dimensional vortex states, offering a high level of programmable dynamical reconfigurability.

The partial replacement of the A-site by divalent methylenediammonium cations inhibits ion migration and photoinduced halide segregation in wide-bandgap perovskites. Single-junction devices achieve a certified power conversion efficiency of 22.71%, whereas perovskite/Cu(In,Ga)Se₂ tandem devices exhibit an efficiency of 30.13% in a four-terminal architecture.

A miniaturized diffractive neural network is fabricated on the distal facet of a multimode fibre, allowing all-optical image transportation through the fibre. With a compact footprint of 150 μm × 150 μm, the system allows the transportation of images with a minimum feature size of 4.90 μm and shows transfer learning capabilities when transporting images of biological cells projected by spatial light modulators.

A Fourier-transform imaging spectrometer enables two-dimensional spectral Brillouin imaging at a throughput of up to 40,000 spectra per second over a 300 × 300 µm² field of view.

Dense three-dimensional integration of photonics and electronics results in a high-speed (800 Gb s⁻¹) data interface for semiconductor chips that features 80 communication channels and consumes only tens of femtojoules per transmitted bit.

Using a grating-based mode-splitting and reflector approach, a bidirectional chip-scale nanophotonic Kerr-resonator circuit that consumes 97% of the pump power to generate a soliton frequency comb at approaching unit efficiency with 65% conversion efficiency is reported.

Combining space topology and time topology, topological states that are localized simultaneously in space and time are theoretically and experimentally demonstrated, potentially enabling the space-time topological shaping of light waves with applications in spatiotemporal wave control for imaging, communications and topological lasers.

Cluster states with three-dimensional connectivities are realized by selecting specific time–frequency mode bases for multimode quantum light. The cluster state generation is verified by nullifier measurements as well as full inseparability tests across all possible bipartitions.

Researchers demonstrated integrated non-magnetic isolators with 24.5-dB contrast, –2.16-dB insertion loss and 2-THz (16-nm) optical bandwidth.

The researchers exploit exciton-to-trion conversion in ångström-thick semiconductors for all-optical detection of electrical activity in cardiomyocyte cultures. This approach affords high temporal resolution and paves the way for elusive label-free all-optical voltage-sensing applications of two-dimensional semiconductor materials in the biological domain.