Light-based processing and machine learning featured heavily in San Diego at the 2024 SPIE Optics + Photonics conference. Enthusiasm was coupled with questions related to the real-world applicability and the merits of linear vs non-linear, and all-optical vs hybrid, approaches.

Following first lasing at LCLS-II — a coherent X-ray laser source driven by a 700-m superconducting linear accelerator — several upgrades are already in the works. Nature Photonics spoke to LCLS director Mike Dunne about LCLS-II commissioning hurdles as well as future plans.

A ring laser gyroscope, located at the Geodetic Observatory Wettzell in Southern Germany, measures variations in the Earth's rotation. Nature Photonics spoke to a key researcher on the project, Ulrich Schreiber, about the system's birth, teething issues, and how it may one day probe the El Nino effect.

Allen Weeks, Director General of the Extreme Light Infrastructure European Research Infrastructure Consortium, talks to Nature Photonics about the founding and future of the high-power-laser facilities, and stimulating a resurgence of physics in new EU member countries.

Geoffroy Lerosey, co-founder and CEO/CSO of Greenerwave, shares how tunable metasurfaces may shake up industries from automotive to wireless communications.

George Palikaras, President and CEO of Meta Materials Inc., discusses the challenges of commercializing metamaterials, learned on the path from a small start-up to a Nasdaq-listed company.

Nature Photonics spoke to Aydogan Ozcan about the rise of artificial intelligence-enabled optics and the hurdles ahead.

Franky So, from North Carolina State University, explains some hard truths for solution-processed emitters, but also that, fundamentally, there is no reason why OLEDS can't 'make it'.