Journal of Physics Conference Series

Continuum-continuum transitions between resonant states using the RABITT technique

A Jiménez, Luca Argenti, Fernando Martı́n

Published Apr 10, 2014• 0 citations

Abstract

We present a study of radiative continuum-continuum transitions in helium in the presence of doubly-excited states by using the attosecond RABITT technique beyond the Single Active Electron approximation. On the one hand, transition amplitudes between correlated continuum states are calculated both by direct numerical solution of the time-dependent Schrodinger equation as well as with a two-photon perturbative model. The effect of autoionizing states on the sideband phaseshift is thus analyzed. On the other hand, we apply the soft-photon approximation to quantify the effects the IR probe intensity on the sideband non-resonant overtone components.

DOI: 10.1088/1742-6596/488/2/022014

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Journal of Physics Conference Series

Continuum-continuum transitions between resonant states using the RABITT technique

A Jiménez, Luca Argenti, Fernando Martı́n

Published Apr 10, 2014• 0 citations

Publisher

Abstract

DOI: 10.1088/1742-6596/488/2/022014

Related papers

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The strong coupling between two autoionizing states in helium is studied theoretically with the pump-probe scheme. An isolated 100-as XUV pulse is used to excite helium near the

2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)

resonance state in the presence of an intense infrared (IR) laser. The laser field introduces strong coupling between

2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)

and

2{p}^{2}{(}^{1}\phantom{\rule{0.16em}{0ex}}S)

states. The IR also can ionize helium from both autoionizing states. By changing the time delay between the XUV and the IR pulses, we investigated the photoelectron spectra near the two resonances. The results are used to explain the recent experiment by Gilbertson et al. [Phys. Rev. Lett. 105, 263003 (2010)]. Using the same isolated attosecond pulse and a 540-nm laser, we also investigate the strong coupling between

2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)

and

2{s}^{2}{(}^{1}\phantom{\rule{0.16em}{0ex}}S)

by examining how the photoelectron spectra are modified versus the time delay and the possibility of observing Autler-Townes doublet in such experiments.