New tools for extreme ultrafast science and applications

Ultrafast science is about looking at nature at its core, where time-resolved measurements enable accessing ultrafast processes in matter, from femtosecond molecular dynamics to sub-femtosecond electronic motion. Like in other sciences, such ability relies on technological breakthroughs, on new and inventive tools not only for seeing but also for touching and moulding the elusive microscopic world. In all these tools, controlling and measuring light – the driving force for pushing and pulling at the most elemental blocks of matter – plays a key role.

Intense laser pulses containing only a few precise oscillations of the electric field of light are behind many groundbreaking results in science and technology. Their extreme interaction with matter has resulted in the generation of even shorter pulses via the process of high-harmonic generation, effectively pushing ultrafast science into the attosecond realm, 1000 times faster than the femtosecond. First performed in gases, attosecond techniques have enabled the observation and manipulation of electrons inside the atoms themselves, providing ultimate control of physical systems and devices. Recent breakthroughs in intense laser-matter interaction in solids show promise for taking electronics to the petahertz range, 1 million times faster than present-day gigahertz electronics.

Despite their huge potential, the widespread use of broadband few-cycle laser pulses has been hampered by limitations and difficulties in pulse measurement technology. The dispersion scan (d-scan) technique developed in our group presents a new paradigm in ultrashort pulse measurement and control that effectively came to solve many of the problems associated with traditional pulse characterization methods, enabling the measurement and compression of femtosecond pulses comprising only a single oscillation of the electric field. In this talk, I will present key aspects of the d-scan technique, recent applications and results, from ultrafast excitation and spectroscopy in low-dimensional and magnetic materials to new approaches in biomedical imaging and the first all-optical measurement of the electric field of light itself. The ultrafast sources and disrupting techniques developed over the last few years will enable tackling key challenges in attosecond science and technology, closing the gap between cutting-edge attophysics research in solid materials and present-day vacuum-based characterization methods, establishing new methods for the in-situ observation and coherent control of strong-field laser-matter interaction, and bringing forth new attosecond devices for the ultrafast scientific community and for emerging industrial applications.