Volume 12 Issue 11, November 2018

Emil Wolf died in June 2018 at the age of 95. The father of optical coherence theory was at the University of Rochester for nearly 60 years. A memorial in August at the university attracted more than 150 attendees from around the world.

A single silicon double injection resonator provides flexible response shapes, large free spectral range and tolerance to temperature deviations and fabrication defects, paving the way for high-performance integrated photonics.

Spatial multiplexing enables the simultaneous generation of several low-noise frequency combs in a single microresonator, promising to enhance a host of applications such as multidimensional coherent spectroscopy.

A boom of activity in the deployment of photonics in space is underway. That was the clear message from this year’s European Conference on Optical Communication in Italy.

Recent achievements and future opportunities for light as a propulsion scheme for space vehicles is discussed.

Starting with a desired optical output it is possible to use computational algorithms to inverse design devices. The approach is reviewed here with an emphasis on nanophotonics.

An integrated silicon photonic optical gyroscope achieves two orders of magnitude size reduction and a factor of thirty better phase-shift sensitivity using reciprocal sensitivity enhancement.

A nonlinear coherent spectroscopy that uses three slightly different repetition-rate frequency combs is demonstrated. A 2D spectrum with comb resolution is generated using only 365 milliseconds of data, almost 600 times faster than previous approaches.

Perovskite quantum dots (QDs) are synthesized via an anion-exchange process where CsPbBr₃ is used to realize a highly efficient red light-emitting diode (LED). The perovskite QD-based LED exhibits the highest external quantum efficiency of more than 20% compared with perovskite LEDs.

Synchronization of two optical microresonator frequency combs coupled over distances larger than 20 metres is experimentally realized, opening up applications of microresonator combs and offering a chip-based photonic platform for exploring complex nonlinear systems.

A broadband multi-frequency Fabry–Pérot laser diode, when coupled to a high-Q microresonator, can be efficiently transformed to an ~100 mW narrow-linewidth single-frequency light source, and subsequently, to a coherent soliton Kerr comb oscillator.

Up to three distinct frequency combs are simultaneously generated from an optical microresonator and a continuous-wave laser, enabling the deployment of dual- and triple-comb-based methods to applications unachievable by current technologies.

Frequency response shaping of a ‘racetrack’ ring resonator is demonstrated using a double injection configuration. Sinusoidal, triangular, square and other response shapes are shown.