Femtosecond self-focusing dynamics measured by three-dimensional phase-retrieval cross correlation

Citation
Tw. Yau et al., Femtosecond self-focusing dynamics measured by three-dimensional phase-retrieval cross correlation, J OPT SOC B, 17(9), 2000, pp. 1626-1635
Citations number
66
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
ISSN journal
0740-3224 → ACNP
Volume
17
Issue
9
Year of publication
2000
Pages
1626 - 1635
Database
ISI
SICI code
0740-3224(200009)17:9<1626:FSDMBT>2.0.ZU;2-U
Abstract
We use a phase-retrieval cross-correlation technique to analyze the spatiot emporal field evolution of self-focused ultrashort pulses. The technique fe atures a new phase-retrieval algorithm based on functional differentiation. Its sensitivity, rapid convergence, and temporal nonreciprocality enable r eliable three-dimensional waveform reconstruction. At less than the critica l power, the experiments verify conventional description of self-focusing a nd give a direct proof of the Kerr-lens mode-locking mechanism. In contrast , for pulses with peak power much more than the critical power, nearly unif orm self-focusing and quasi-stable single-filament trapping to a universal beam diameter were observed. The trapping can be explained by the saturatio n of the nonlinear refractive-index change at Delta n similar to 7 x 10(-5) . The saturation is verified by an independent cross-polarization modulatio n measurement. (C) 2000 Optical Society of America [S0740-3224(00)02108-1].