Recently, the research group helmed by Professor Liu Yunquan from the School of Physics at Peking University released a review article in Nature Reviews Physics. This article offers a comprehensive overview of the advancements in structured-light-driven ultrafast physics. It zeroes in on how structured light fields, operating in both temporal and spatial domains, can regulate bound and free electron systems. The article also highlights their applications in key areas, including strong-field ionization, high-order harmonic generation, and free-electron spectroscopy.

The study emphasizes that spatiotemporally structured light fields present a groundbreaking approach to uncovering ultrafast electron dynamics within matter. This is achieved through precise control over laser parameters like amplitude, polarization state, and phase. For example, leveraging multi-wavelength spatiotemporal synthesis techniques based on Mach-Zehnder interferometers, researchers can create time-structured light fields. These include orthogonal bichromatic fields and circularly polarized bichromatic fields, enabling attosecond-level resolution in the observation of electron tunneling events.

Moreover, spatial structured light fields, such as longitudinal vortex beams and optical skyrmions, can be generated using components like q-plates and spatial light modulators. These fields imbue photons with quantized orbital angular momentum, paving the way for novel methods of coherent control over high-order harmonics.

Furthermore, spatiotemporally structured light fields hold tremendous promise in areas like the regulation of extreme ultraviolet topological light fields and the generation of free-electron vortex arrays. They offer a wealth of experimental tools and theoretical frameworks, thereby enriching the field of ultrafast physics research.