Femtosecond laser interacts with material shows nonlinear absorption and low thermal diffusion due to the ultrashort pulse width and ultrahigh peak power,which makes it important in the manufacturing of high-precision micro-nano devices.An ultrafast dynamic model for transient photoionization and non-equilibrium heat transfer of femtosecond laser pulses interacting with fused silica was established.By numerical solution,the spatio-temporal evolution of carrier density and non-equilibrium electron and phonon temperature of fused silica excited under femtosecond laser single pulse was obtained,and the nearly linear regulation law of electron-phonon coupling time with laser energy density and pulse width under non-equilibrium conditions was obtained.The variation laws of transient electron thermal conductivity,thermal capacity and electron-phonon coupling coefficient were further investigated in details.And the above simulation results were analyzed and discussed.
关键词
飞秒激光脉冲/瞬态光电离/超快传热/双温模型
Key words
femtosecond laser pulse/transient photoionization/ultrafast heat transfer/two-temperature model
维普
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