Reviews & Analysis

Excitation and gate tuning of terahertz plasmons in dual-layer graphene integrated into on-chip telecom photonic waveguides using infrared lasers has now been demonstrated. This may open the door to atomically thick optoelectronic devices for security, tomography or data processing.

The science of superoscillations and the creation of local regions of light on a subwavelength scale is attracting attention for new forms of super-resolution microscopy and stiffer optical traps.

A theoretical analysis of asymmetric dressed quantum dots in a photonic crystal cavity suggests that the system could form a new type of solid-state terahertz laser. However, an experimental realization will likely require advances in fabrication technology.

This Review covers key advancements in X-ray ptychographic microscopy and tomography over the past ten years. Potential applications in the life and materials sciences, the latest concepts and future developments are also discussed.

The field of machine learning potentially brings a new set of powerful tools to optical communications and photonics. However, to separate hype from reality it is vital that such tools are evaluated properly and used judiciously.

Plasmonic antennas store energy by localizing light to nanoscale volumes. A plasmon’s oscillating electrons can scatter directly into a semiconductor, transferring the captured energy in less than ten femtoseconds.

Optically generated local phase changes in methylammonium lead iodide produce a transient quantum-well-like structure with robust optical gain. The result is a perovskite laser that supports continuous-wave lasing under optical pumping.

General concepts and recent developments of parity–time symmetry in classical photonics are reviewed.

The progress on non-reciprocal photonic devices enabled by temporal modulation is reviewed.

Topological photonic structures offer unique features such as reflection-free and non-reciprocal devices. This Review highlights the experimental progress in the relatively new field of photonic topology.

Diffraction-free light-sheet beams, strongly confined in one axis, are typically thought to self-bend during propagation in free space and cannot be made flat. Now, diffraction-free planar light sheets in air have been realized by exploiting polychromatic pulsed beams.

The demonstration of strong coupling between two nuclear polariton modes in the X-ray spectral region using two coupled cavities each containing a thin layer of iron brings new opportunities for exploring quantum science.

At the 24th General Congress of the International Commission for Optics in Tokyo, photonics-based sensing and simulations were shown to benefit research into phenomena that span the nanometre to astronomical range.

Optical trapping of ions is relatively new and has been limited to a few milliseconds so far. Now researchers have trapped a single barium ion for several seconds, putting experiments with ultracold atoms and ions within reach.

Applications of the concept of structured light are not limited to optical communications, metrology, and probing and sensing, they can also go beyond optics.

Single-molecule detection commonly requires focused laser beams because of the small absorption cross-sections of dye molecules. Now, researchers have shown that thousands of dye molecules in nanoparticles can transfer light excitation to a single acceptor dye, enabling single-molecule detection at sunlight excitation power.