Time-Resolved Observation of Energy Deposition in Fused Silica by Ultrashort Laser Pulses in Single and Cumulative Regime

Cyril Mauclair (1) , Konstantin Mishchik (1) , Alexandre Mermillod-Blondin (1) , Jörn Bonse (2) , Arkadi Rosenfeld (2) , Ingolf-Volker Hertel (3) , Eric Audouard (1) , Razvan Stoian (1)

1 LHC - Laboratoire Hubert Curien
2 MBI - Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie
3 MBI - Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie

When femtosecond laser pulses are focused in the bulk of transparent materials (glasses), deposition of energy on a restricted volume can occur owing to the non linear character of the laser matter interaction. As a consequence, the possibility to generate micrometer-sized structural modifications arises. Those local changes are often associated with a minute variation in the refractive index which, when positive, enables the fabrication of light guiding components in three dimensions through simple laser translation. Although the first corresponding experimental demonstration approaches fifteen years of age, the complete picture of the dynamics and the proc- esses leading to the local refractive index changes has still to be drawn to reach an optimal control of the laser-induced modification process. In this report, the laser-dielectric interaction is followed on an ultrashort time scale with the help of a unique time-resolved side-imaging technique allow- ing for absorption and phase contrast detection. Experimental observation of an absorptive elec- tronic cloud in the first moments of the interaction along with the launch of a pressure wave after a few ns is reported. These physical objects are shown to be reliable indicators of the success of the energy transfer to the lattice which largely depends on the pulse temporal envelope.

Domains: Optics / Photonic

Cyril Mauclair, Konstantin Mishchik, Alexandre Mermillod-Blondin, Jörn Bonse, Arkadi Rosenfeld, et al.. Time-Resolved Observation of Energy Deposition in Fused Silica by Ultrashort Laser Pulses in Single and Cumulative Regime. Conference on Lasers and Electro-Optics (CLEO), May 2010, San José, CA, United States. pp.CMBB7. ⟨ujm-00494954⟩