抄録
The propagation of ultrashort laser pulses in water has been investigated with the extended nonlinear Schrödinger equation and the electron density equation. With the model that incorporates the diffraction, normal group-velocity dispersion, multiphoton absorption, self-focusing and defocus of light by the generated free electrons, we examined numerically the spatio-temporal development of the on-axis light intensity along the propagation and the laser-induced electron plasma. Simulation of the underlying dynamics of the ultrashort laser propagation in water reveals that the self-focusing interplays competitively with the laser-induced optical breakdown. Moreover, the laser energy, its duration and focusing geometry determine in combination the structure of plasma filament and the reshaping of energy fluence. The results may provide a better understanding and application of the ultrashort laser pulses in medicine.
