Seminars

Phase resolved attosecond photoionization

by Dr. Yann Mairesse (CELIA, Université Bordeaux I, France)

Thursday, May 19, 2011 from to (Europe/Berlin)
at AER 19/3.11
Description
High order harmonic generation is a natural source of trains of
attosecond pulses in the extreme ultraviolet. The main technique used
to characterize these attosecond pulses is the RABBITT technique
(Resolution of Attosecond Beatings By Interference of Two-photon
Transitions), in which a rare gas is photoionized by the attosecond
pulse train in the presence of an additional weak infrared field.
By controlling the delay between the infrared and the XUV light, it is
possible to retrieve the relative phase of the different harmonics
constituting the attosecond pulse train, and thus the temporal
structure of the attosecond pulses.
Alternatively, the RABBITT method can be used to characterize the
photoionization process itself: using a well characterized attosecond
pulse train to photoionize a more complex target (molecular gas,
solid), information on the phase of the photoionization process can be
retrieved. We will show how this method can be used to reveal a phase
jump in the attosecond photoionization of nitrogen molecules in the
vicinity of a resonance. We will also discuss the current
extension of such measurements to the case of solid targets.