Articles in 2017

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.

Nature Photonics spoke to Demetrios Christodoulides, of CREOL, The College of Optics & Photonics, University of Central Florida, about the birth of the parity–time-symmetry concepts in optics and the challenges and prospects on the path ahead.

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.

The exploitation of non-Hermitian quantum physics concepts in classical photonics has spawned much research activity during 2017. We conclude the year with a focus issue on parity–time symmetry and concepts with overlapping goals, in particular topological and non-reciprocal photonics.

The role of direct plasmonic coupling in hot-electron generation at Ag/TiO₂ interfaces is clarified by two-photon photoemission spectroscopy.

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

Attosecond electron pulse trains in electron microscopy are demonstrated through the coupling of phase-locked multicolour optical fields with electron pulses. A new variant of quantum state tomography for free-electron ensembles is established.

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.

Optically pumped continuous-wave lasing is achieved in methylammonium lead iodide (MAPbI₃) distributed feedback lasers that are maintained below the MAPbI₃ tetragonal-to-orthorhombic phase transition temperature of 160 K.