Adaptive correction of a tightly focused, high-intensity laser beam by use of a third-harmonic signal generated at an interface

Thomas A. Planchon (1) , W. Amir (1) , J. J. Field (1) , C. G. Durfee (1) , J. A. Squier (1) , Pascal Rousseau (2) , Olivier Albert (3) , Gérard Mourou (3)

1 Colorado School of Mines
2 CUOS - Center for Ultrafast Optical Sciences
3 LOA - Laboratoire d'optique appliquée

By using the third-harmonic signal generated at an air-dielectric interface, we demonstrate a novel way of correcting wavefront aberrations induced by high-numerical-aperture optics. The third harmonic is used as the input physical parameter of a genetic algorithm working in closed loop with a 37-actuator deformable mirror. This method is simple and reliable and can be used to correct aberrations of tightly focused beams, a regime where other methods have limitations. Improvement of the third-harmonic signal generated with an f/1.2 parabolic mirror by 1 order of magnitude is demonstrated.

Domains: Optics [physics.optics]

Thomas A. Planchon, W. Amir, J. J. Field, C. G. Durfee, J. A. Squier, et al.. Adaptive correction of a tightly focused, high-intensity laser beam by use of a third-harmonic signal generated at an interface. Optics Letters, 2006, 31 (14), pp.2214-2216. ⟨10.1364/OL.31.002214⟩. ⟨hal-00554196⟩