Experimental observation of fractional echoes

G. Karras (1) , E. Hertz (1) , F. Billard (1) , B. Lavorel (1) , G. Siour (2, 3) , J. -M. Hartmann (2, 3) , O. Faucher (1) , Erez Gershnabel , Yehiam Prior , Ilya Sh. Averbukh

1 ICB - Laboratoire Interdisciplinaire Carnot de Bourgogne
2 LISA (UMR_7583) - Laboratoire Interuniversitaire des Systèmes Atmosphériques
3 IPSL (FR_636) - Institut Pierre-Simon-Laplace

We report the observation of fractional echoes in a double-pulse excited nonlinear system. Unlike standard echoes, which appear periodically at delays which are integer multiples of the delay between the two exciting pulses, the fractional echoes appear at rational fractions of this delay. We discuss the mechanism leading to this phenomenon, and provide experimental demonstration of fractional echoes by measuring third harmonic generation in a thermal gas of CO₂ molecules excited by a pair of femtosecond laser pulses.

Mots clés: Physics - Optics; Physics - Atomic Physics; Physics - Chemical Physics

Domaines: Planète et Univers [physics]

G. Karras, E. Hertz, F. Billard, B. Lavorel, G. Siour, et al.. Experimental observation of fractional echoes. Physical Review A, 2016, 94, 148, p. 1-16. ⟨10.1103/PhysRevA.94.033404⟩. ⟨insu-03737479⟩