When time measurement is set to Attosecond regime

The work of the three laureates of the 2023 Nobel Prize in Physics emerged within a scientific context where the movement of electrons in matter (atoms, molecules, or solids) was inaccessible to measurement by conventional time-resolved methods. To overcome this inaccessibility, it was necessary to develop beneath the femtosecond threshold, thereby creating a frontier between intense field physics and nonlinear optics, generating high-order harmonics falling within the attosecond range. Achieving this required highly advanced scientific and technological means to transform electromagnetic excitation fields, typically with femtosecond periods, which fall within the visible to near-infrared range, into pulses within the sub-femtosecond regime. These excitation fields interact with gaseous systems, and through this interaction, pulses are generated in the form of High-Order Harmonics (HOHG), wich extend to higher frequency ranges, specifically the extreme ultraviolet (XUV) region.