First-principles electron dynamics simulation for optical breakdown of dielectrics under an intense laser field
First-principles electron dynamics simulation for optical breakdown of dielectrics under an intense laser field
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DOI：
10.1103/physrevb.77.165104
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发表时间：
2008-04
影响因子：
3.7
通讯作者：
T. Otobe;M. Yamagiwa;J. Iwata;K. Yabana;T. Nakatsukasa;G. Bertsch
中科院分区：
文献类型：
--
作者：
T. Otobe;M. Yamagiwa;J. Iwata;K. Yabana;T. Nakatsukasa;G. Bertsch
利用第一性原理计算了强激光场作用下金刚石的光学介电击穿。我们采用含时密度泛函理论，在真实的时间和真实的空间中求解含时Kohn\char21{}Sham方程.对于低强度，电离符合Keldysh公式。计算表明，随着激光强度的增加，电子动力学发生了质的变化，从低强度的介电屏蔽到高于7\ifmmode\times\else\texttimes\fi {}{10}^{14}\text{ }\text{W}/{\text{cm}}^{2}$的光学击穿。在脉冲之后，被激发进入导带的电子表现出持续数十飞秒的相干等离子体振荡。
We present a first-principles calculation for an optical dielectric breakdown in a diamond, which is induced by an intense laser field. We employ the time-dependent density-functional theory by solving the time-dependent Kohn\char21{}Sham equation in real time and real space. For low intensities, the ionization agrees well with the Keldysh formula. The calculation shows a qualitative change of electron dynamics as the laser intensity increases, from dielectric screening at low intensities to optical breakdown at and above $7\ifmmode\times\else\texttimes\fi{}{10}^{14}\text{ }\text{W}/{\text{cm}}^{2}$. Following the pulse, the electrons excited into the conduction band exhibit a coherent plasma oscillation that persists for tens of femtoseconds.