It might not be clear from the reporting but I guess the paper‘s title (linked from the bottom of the article) might give a clue already: „Acousto-optic modula

It might not be clear from the reporting but I guess the paper‘s title (linked from the bottom of the article) might give a clue already: „Acousto-optic modulation of gigawatt-scale laser pulses in ambient air“, https://www.nature.com/articles/s41566-023-01304-y https://www.nature.com/articles/s41566-023-01304-y (open access) Here’s an excerpt from the abstract: „Modern photonics […] can involve parameter regimes where the wavelength or high optical powers involved restrict control due to absorption, light-induced damage or optical nonlinearity in solid media. Here we propose to circumvent these constraints using gaseous media tailored by high-intensity ultrasound waves. We demonstrate an implementation of this approach by efficiently deflecting ultrashort laser pulses using ultrasound waves in ambient air, without the use of transmissive solid media. At optical peak powers of 20 GW, exceeding previous limits of solid-based acousto-optic modulation by about three orders of magnitude, we reach a deflection efficiency greater than 50% while preserving excellent beam quality.“