Field-free molecular alignment detection by 4f coherent imaging

Julien Houzet (1) , Franck Billard (1) , Edouard Hertz (1) , David Chateau (1) , Frédéric Chaussard (1) , Bruno Lavorel (1) , Olivier Faucher (1)

1 ICB - Laboratoire Interdisciplinaire Carnot de Bourgogne

Time-resolved detection of field-free molec- ular alignment is investigated by phase contrast. The technique based on a 4f imager operating as an inverted Zernike spatial filter makes it possible to discriminate be- tween positive and negative molecular alignment revivals produced in a linear molecule. The measurements are performed in a way that minimizes the contamination of the signal by the plasma generated during the align- ing pulse. The observations are supported by a semi- analytical model, from which the degree of alignment produced at the beam focus is estimated.

Mots clés: molecular alignment; femtosecond phenomena; Ultrafast nonlinear optics; phase-contrast; Zernike

Domaines: Physique Atomique [physics.atom-ph]

Julien Houzet, Franck Billard, Edouard Hertz, David Chateau, Frédéric Chaussard, et al.. Field-free molecular alignment detection by 4f coherent imaging. Applied Physics B Photophysics and Laser Chemistry, 2012, 108, pp.897-902. ⟨10.1007/s00340-012-5203-6⟩. ⟨hal-00761282⟩