|
|||||
|
|
Critical power for self-focussing of a femtosecond laser pulse in helium |
|
| Authors: | J Bernhardt PT Simard HL Xu A Azarm SL Chin |
| Institution: | a Centre d’Optique, Photonique et Laser (COPL) and Département de physique, de génie physique et d’optique, Université Laval, Québec, QC, Canada G1V 0A6 b Institute of Modern Optics, Nankai University, Tianjin 300071, PR China c Defence Research and Development Canada - Valcartier, 2459 Pie-XI Blvd North, Québec, QC, Canada G3J 1X5 |
| Abstract: | The critical power for self-focussing of a femtosecond laser pulse in helium has been measured using the moving focus method. The experimental value is  (1 atm) ∼268 GW. Using this value, the nonlinear refractive index is inferred to be  ∼ 3.6 × 10-21 cm2/W. In addition, the plots of the electron densities versus energy and pressure have also been used to determine the critical power of helium, based on the intensity clamping of the filamentation process. The value agrees well with the one by the moving focus method. |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ | |