中国物理B ›› 2020, Vol. 29 ›› Issue (1): 17801-017801.doi: 10.1088/1674-1056/ab577c

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Non-parabolic effect for femtosecond laser-induced ultrafast electro-absorption in solids

Li-Bo Liu(刘利博), Hong-Xiang Deng(邓洪祥), Xiao-Tao Zu(祖小涛), Xiao-Dong Yuan(袁晓东), Wan-Guo Zheng(郑万国)   

  1. 1 School of Physics, University of Electronic Science and Technology of China, Chengdu 610054, China;
    2 Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900, China
  • 收稿日期:2019-07-05 修回日期:2019-09-05 出版日期:2020-01-05 发布日期:2020-01-05
  • 通讯作者: Hong-Xiang Deng E-mail:denghx@uestc.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 61505023).

Non-parabolic effect for femtosecond laser-induced ultrafast electro-absorption in solids

Li-Bo Liu(刘利博)1, Hong-Xiang Deng(邓洪祥)1,2, Xiao-Tao Zu(祖小涛)1, Xiao-Dong Yuan(袁晓东)2, Wan-Guo Zheng(郑万国)2   

  1. 1 School of Physics, University of Electronic Science and Technology of China, Chengdu 610054, China;
    2 Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900, China
  • Received:2019-07-05 Revised:2019-09-05 Online:2020-01-05 Published:2020-01-05
  • Contact: Hong-Xiang Deng E-mail:denghx@uestc.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 61505023).

摘要: A theoretical study for femtosecond laser-induced ultrafast electro-absorption of bulk solids is presented. Our numerical results show that, in the case of low intensity of the pump laser where the interaction between the pump laser and solids is in the multi-photon regime, the energy band of solids can be approximately taken as a parabolic band and electro-absorption spectrums from the parabolic band and real band are nearly the same. While, in the case of high intensity where the interaction is in the tunneling regime, spectrums from the parabolic band and real band are quite different. The physical mechanism for the difference in the tunneling regime is found. We find that the non-parabolic parts of the real energy band and Bragger scattering of electrons near the first Brillouin zone boundaries, which are neglected in previous studies, strongly influence the electro-absorption spectrum in the tunneling regime. These two physical processes cause the difference of spectrums. Our theoretical results are in accordance with the experiment result.

关键词: ultrafast electro-absorption, red-shift of absorption edge, Bragger scattering effect, multi-photon process

Abstract: A theoretical study for femtosecond laser-induced ultrafast electro-absorption of bulk solids is presented. Our numerical results show that, in the case of low intensity of the pump laser where the interaction between the pump laser and solids is in the multi-photon regime, the energy band of solids can be approximately taken as a parabolic band and electro-absorption spectrums from the parabolic band and real band are nearly the same. While, in the case of high intensity where the interaction is in the tunneling regime, spectrums from the parabolic band and real band are quite different. The physical mechanism for the difference in the tunneling regime is found. We find that the non-parabolic parts of the real energy band and Bragger scattering of electrons near the first Brillouin zone boundaries, which are neglected in previous studies, strongly influence the electro-absorption spectrum in the tunneling regime. These two physical processes cause the difference of spectrums. Our theoretical results are in accordance with the experiment result.

Key words: ultrafast electro-absorption, red-shift of absorption edge, Bragger scattering effect, multi-photon process

中图分类号:  (Spectroscopy of solid state dynamics)

  • 78.47.-p
72.20.Ht (High-field and nonlinear effects) 42.65.Ky (Frequency conversion; harmonic generation, including higher-order harmonic generation) 78.40.Fy (Semiconductors)