Effect of Pulse Width and Fluence of Femtosecond Laser on Electron--Phonon Relaxation Time
FANG Ran-Ran1, ZHANG Duan-Ming1 WEI Hua2, LI Zhi-Hua1, YANG Feng-Xia1, TAN Xin-Yu1
1School of Physics, Huazhong University of Science and Technology, Wuhan 4300742State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071
Effect of Pulse Width and Fluence of Femtosecond Laser on Electron--Phonon Relaxation Time
FANG Ran-Ran1, ZHANG Duan-Ming1 WEI Hua2, LI Zhi-Hua1, YANG Feng-Xia1, TAN Xin-Yu1
1School of Physics, Huazhong University of Science and Technology, Wuhan 4300742State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071
摘要The electron--phonon relaxation time as functions of pulse width and fluence of femtosecond laser is studied based on the two-temperature model. The two-temperature model is solved using a finite difference method for copper target. The temperature distribution of the electron and the lattice along with space and time for a certain laser fluence is presented. The time-dependence of lattice and electron temperature of the surface for different pulse width and different laser fluence are also performed, respectively. Moreover, the variation of heat-affected zone per pulse with laser fluence is obtained. The satisfactory agreement between our numerical results and experimental data indicates that the electron--phonon relaxation time is reasonably accurate with the influences of pulse width and fluence of femtosecond laser.
Abstract：The electron--phonon relaxation time as functions of pulse width and fluence of femtosecond laser is studied based on the two-temperature model. The two-temperature model is solved using a finite difference method for copper target. The temperature distribution of the electron and the lattice along with space and time for a certain laser fluence is presented. The time-dependence of lattice and electron temperature of the surface for different pulse width and different laser fluence are also performed, respectively. Moreover, the variation of heat-affected zone per pulse with laser fluence is obtained. The satisfactory agreement between our numerical results and experimental data indicates that the electron--phonon relaxation time is reasonably accurate with the influences of pulse width and fluence of femtosecond laser.
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2008, Vol. 25 
