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Journal articles
Second-order cascading-assisted filamentation and controllable supercontinuum generation in birefringent crystals
Abstract : We experimentally investigate filamentation and supercontinuum generation in a birefringent medium (BBO crystal), in the self-focusing regime where intrinsic cubic nonlinearity is either enhanced or reduced by the second-order cascading due to phase-mismatched second harmonic generation. We demonstrate that the supercontinuum spectral extent is efficiently controlled by varying the phase mismatch parameter. In the range of negative phase mismatch, we achieve full control of the blue-shifted spectral broadening, which is very robust and independent on the input pulse energy. In the range of positive phase mismatch, both the blue-shifted and the red-shifted spectral broadenings are controlled simultaneously, however showing a certain dependence on the input pulse energy. The results are interpreted in terms of complex interplay between the self-phase-matched second harmonic generation, which is a process inherent to narrow ultrashort pulsed laser beams and concurrent self-steepening processes which arise from cubic and cascaded-quadratic nonlinearities.
https://hal-ensta-paris.archives-ouvertes.fr//hal-01508433
Contributor : Aurélien Houard <>
Submitted on : Friday, April 14, 2017 - 10:44:29 AM
Last modification on : Wednesday, October 14, 2020 - 4:19:12 AM
Contributor : Aurélien Houard <>
Submitted on : Friday, April 14, 2017 - 10:44:29 AM
Last modification on : Wednesday, October 14, 2020 - 4:19:12 AM