Measurement of high order Kerr refractive index of major air components

V. Loriot (1) , E. Hertz (1) , O. Faucher (1) , B. Lavorel (1)

1 ICB - Laboratoire Interdisciplinaire Carnot de Bourgogne

We measure the instantaneous electronic nonlinear refractive index of N2 , O2 , and Ar at room temperature for a 90 fs and 800 nm laser pulse. Measurements are calibrated by post-pulse molecular alignment through a polarization technique. At low intensity, quadratic coefficients n2 are determined. At higher intensities, a strong negative contribution with a higher nonlinearity appears, which leads to an overall negative nonlinear Kerr refractive index in air above 26 TW/cm2 .

Mots clés: Molecular alignment; Femtosecond phenomena; Plasmas; Ultrafast nonlinear optics; Self-focusing; Optical Kerr effect

Domaines: Physique Atomique [physics.atom-ph]

V. Loriot, E. Hertz, O. Faucher, B. Lavorel. Measurement of high order Kerr refractive index of major air components. Optics Express, 2009, 17 (16), pp.13429. ⟨hal-00410677⟩