Physical Society Colloquium

Attosecond imaging with x-rays

Peter Abbamonte

Department of Physics
University of Illinois at Urbana-Champaign

The dawn of the 21st century has witnessed the development of the attosecond[*]laser, which has promised a revolution in ultrafast science. Cited by the journal Nature as the 22nd milestone in the history of light (the publication of Maxwell's equations being milestone #2), the attosecond laser has heralded a new age of "attoscience" in which electron motion may be studied in real time.

In this talk I will present an alternative approach to attoscience based on inelastic x-ray scattering (IXS). Rather than using explicitly time-resolved techniques, our approach uses x-ray scattering to probe excitations in the domain of frequency and momentum, and then uses state-of-the-art reconstruction algorithms to generate images of electron dynamics in real space and time with attosecond time resolution. I will summarize our use of this technique to image plasma oscillations in liquid water, excitons in insulators, and to measure the effective fine structure constant of graphene. I will close by discussing fundamental connections to the concepts of causality, entropy, and the arrow of time in nature.

[*] 1 attosecond = 10^-3 femtosecond = 10^-18 sec.