Title: Probing Electronic Binding Potentials with Attosecond Photoelectron Wavepackets

D. Kiesewetter [1], R.R. Jones [2], A. Camper [1], S.B. Schoun [1], P. Agostini[1], and L.F. DiMauro[1]

[1]The Ohio State University, Columbus, OH 43210, USA

[2]University of Virginia, Charlottesville, VA 22904, USA

Abstract:

The central goal of attosecond science is to visualize, understand, and ultimately control electron dynamics in matter over the fastest relevant time-scales. To date, numerous schemes have demonstrated exquisite temporal resolution, on the order of 10 attoseconds, in measurements of the response of photo-excited electrons to time-delayed probes. However, attributing this response to specific dynamical mechanisms is difficult, requiring guidance from advanced calculations. Here we show that energy transfer between an oscillating field and low-energy attosecond photoelectron wavepackets directly provides coarse-grained information on the effective binding potential from which the electrons are liberated. We employ a dense XUV harmonic comb to photoionize He, Ne, and Ar atoms and record the electron spectra as a function of the phase of a mid-infrared dressing field. The amplitude and phase of the resulting interference modulations in the electron spectra reveal the average momentum and change in momentum of the electron wavepackets during the first quarter-period of the dressing field after their creation, reflecting the corresponding coarse characteristics of the binding potential.

Status: Published, Nature Physics 14, 68 (2018).