Volume 12 Issue 12, December 2018

A collection of hot rubidium atoms is shown to exhibit non-reciprocal optical transmission due to the interplay between thermal motion and electromagnetically induced transparency.

Applications for optical fibre sensors have evolved beyond physical measurements in the defence, oil, gas and civil engineering sectors to tackle new opportunities in chemical detection.

This Review discusses emerging applications of photonic quantum sensing. The theoretical and experimental developments of quantum reading of classical data, quantum illumination of targets, and optical resolution beyond the Rayleigh limit are described.

When cooled, the ferroelectric perovskite KTN:Li is found to possess a giant refractive index of n > 26 in the visible region.

Self-organization far from thermal equilibrium in a thermo-optical feedback process occurring in a random array of Fabry–Pérot resonators is shown, adding new capability to dynamic self-assembly in creating materials with fine-tuned adaptive responses.

Optical non-reciprocity is experimentally realized with Rb atoms embedded in a ring cavity at room temperature. Random thermal motion of the atoms causes the probe-direction-dependent response assisted by a unidirectional control laser field.

A direct wireless-to-optical receiver in a transparent optical link is achieved, thanks to a subwavelength two-dimensionally localized gap-plasmon mixer encoding wireless information directly onto optical signals.

A quantum walker on a hexagonal glued array of optical waveguides is made inside a glass substrate. The optimal hitting time increases linearly with the layer depth, giving a quadratic speed-up over the hitting performance by classical random walks.

A three-dimensionally entangled Greenberger–Horne–Zeilinger state, where all three photons reside in a qutrit space, is generated by developing a new multi-port in combination with a novel four-photon source entangled in orbital angular momentum.

A linear frequency conversion based on the sudden merging of two distinct split-ring resonators into a single resonator on a rapidly time-variant THz metasurface is reported.

A broadband-light storage technique using the Autler–Townes effect is demonstrated in a system of cold Rb atoms. It overcomes both inherent and technical limitations of the established schemes for high-speed and long-lived optical quantum memories.

Near-infrared perovskite–polymer light-emitting diodes (LEDs) with external quantum efficiencies of up to 20.1% are reported.