Frequency chirp of harmonic and attosecond pulses

Katalin Varjú (1) , Y. Mairesse (2) , B. Carre (2) , M. B. Gaarde (3) , P. Johnsson (1) , S. Kazamias (4) , Rodrigo B. Lopez-Martens (4) , J. Mauritsson (3) , K. J. Schafer (3) , Philippe Balcou (4) , A. L'Huillier (1) , P. Salières (2)

1 Department of Physics
2 SPAM - Service des Photons, Atomes et Molécules
3 Department of Physics and Astronomy [Baton Rouge]
4 LOA - Laboratoire d'optique appliquée

We study the phase of the atomic polarization in the process of high-order harmonic generation. Its dependence on the laser intensity and the harmonic order induce a frequency variation in time (chirp) respectively of the harmonic pulses and attosecond pulses. We review the recent experimental results on the temporal characterization of the harmonic emission and show that measurements performed using very different techniques (like XFROG and RABITT), probing the phase in different parameter spaces, can be connected through the mixed phase derivatives, demonstrating the common underlying physics.

Mots clés: frequency variation; parameter spaces; temporal characterization; frequency chirp; harmonic pulses; atomic polarization phase; attosecond pulses; high-order harmonic generation; harmonic order; laser intensity; harmonic emission

Domaines: Physique Atomique [physics.atom-ph]

Katalin Varjú, Y. Mairesse, B. Carre, M. B. Gaarde, P. Johnsson, et al.. Frequency chirp of harmonic and attosecond pulses. Journal of Modern Optics, 2005, 52 (2 & 3), pp.379 - 394. ⟨10.1080/09500340412331301542⟩. ⟨hal-00574216⟩