A Step Toward Practical Time Crystals

OPTICS & PHOTONICS A platform built from Kerr microresonators and self-injection-locked lasers could take an exotic new phase of matter out of the lab and into real-world applications.

Mapping Methane with Spaceborne Spectrometry

OPTICS & PHOTONICS Data from the TROPOMI imaging spectrometer on the Sentinel-5P satellite have enabled an inventory of the world’s biggest methane emitters—a potentially useful tool in the climate fight.

A Light-Based COVID-19 Breathalyzer

OPTICS & PHOTONICS Prototype device that employs surface-enhanced Raman scattering reportedly obtains results with greater than 95% accuracy—in less than five minutes.