Carrier dynamics and terahertz photoconductivity of doped silicon measured by femtosecond pump-terahertz probe spectroscopy

  • QingLi Zhou
  • YuLei Shi
  • Tong Li
  • Bin Jin
  • DongMei Zhao
  • CunLin Zhang
Article

Abstract

The carrier dynamics and terahertz photoconductivity in the n-type silicon (n-Si) as well as in the p-type Silicon (p-Si) have been investigated by using femtosecond pump-terahertz probe technique. The measurements show that the relative change of terahertz transmission of p-Si at low pump power is slightly smaller than that of n-Si, due to the lower carrier density induced by the recombination of original holes in the p-type material and the photogenerated electrons. At high pump power, the bigger change of terahertz transmission of p-Si originates from the greater mobility of the carriers compared to n-Si. The transient photoconductivities are calculated and fit well with the Drude-Smith model, showing that the mobility of the photogenerated carriers decreases with the increasing pump power. The obtained results indicate that femtosecond pump-terahertz probe technique is a promising method to investigate the carrier dynamics of semiconductors.

Keywords

semiconductor terahertz carrier dynamics 

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Copyright information

© Science in China Press and Springer Berlin Heidelberg 2009

Authors and Affiliations

  • QingLi Zhou
    • 1
  • YuLei Shi
    • 1
  • Tong Li
    • 2
  • Bin Jin
    • 1
  • DongMei Zhao
    • 1
  • CunLin Zhang
    • 1
  1. 1.Beijing Key Laboratory for Terahertz Spectroscopy and Imaging, Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Department of PhysicsCapital Normal UniversityBeijingChina
  2. 2.Department of Electronics EngineeringTianjin University of Technology and EducationTianjinChina

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