Two-photon ionisation processes of rare-gas atoms produced by a superposition of multiple high order harmonics are studied by using a photoelectron spectroscopy technique. Second-order nonlinearity is confirmed by comparing the intensity-dependent photoelectron yields between the linear and nonlinear processes, and the cross sections of these processes are estimated. We also demonstrate the autocorrelation measurement of harmonic envelopes as a preliminary step toward characterisation of an attosecond pulse train.
|Number of pages||9|
|Journal||Applied Physics B: Lasers and Optics|
|Publication status||Published - 2006 May|
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)
- Physics and Astronomy(all)