中国物理B ›› 2011, Vol. 20 ›› Issue (2): 24210-024210.doi: 10.1088/1674-1056/20/2/024210
• CLASSICAL AREAS OF PHENOMENOLOGY • 上一篇 下一篇
高勋, 宋晓伟, 林景全
Gao Xun(高勋)†, Song Xiao-Wei(宋晓伟), and Lin Jing-Quan(林景全)
摘要: Thermal characteristics of tightly-contacted copper--gold double-layer thin film target under ablation of femtosecond laser pulses are investigated by using a two-temperature theoretical model. Numerical simulation shows that electron heat flux varies significantly on the boundary of copper--gold film with different maximal electron temperature of 1.15×103 K at 5 ps after ablating laser pulse in gold and copper films, which can reach a balance around 12.6 ps and 8.2 ps for a single and double pulse ablation, respectively, and in the meantime, the lattice temperature difference crossing the gold--copper interface is only about 0.04×103 K at the same time scale. It is also found that electron--lattice heat relaxation time increases linearly with laser fluence in both single and double pulse ablation, and a sudden change of the relaxation time appears after the laser energy density exceeds the ablation threshold.
中图分类号: (Ultrafast processes; optical pulse generation and pulse compression)