Steering attosecond electron wave packets with light.
Photoelectrons excited by extreme ultraviolet or x-ray photons in the presence of a strong laser field generally suffer a spread of their energies due to the absorption and emission of laser photons. We demonstrate that if the emitted electron wave packet is temporally confined to a small fraction of the oscillation period of the interacting light wave, its energy spectrum can be up- or downshifted by many times the laser photon energy without substantial broadening. The light wave can accelerate or decelerate the electron's drift velocity, i.e., steer the electron wave packet like a classical particle. This capability strictly relies on a sub-femtosecond duration of the ionizing x-ray pulse and on its timing to the phase of the light wave with a similar accuracy, offering a simple and potentially single-shot diagnostic tool for attosecond pump-probe spectroscopy.
Kienberger
R
R
Institut für Photonik, Technische Universität Wien, Gusshausstr. 27, A-1040 Wien, Austria.
Hentschel
M
M
Uiberacker
M
M
Spielmann
Ch
Ch
Kitzler
M
M
Scrinzi
A
A
Wieland
M
M
Westerwalbesloh
Th
T
Kleineberg
U
U
Heinzmann
U
U
Drescher
M
M
Krausz
F
F