中国物理B ›› 2005, Vol. 14 ›› Issue (1): 212-217.doi: 10.1088/1009-1963/14/1/039

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Femtosecond photodeflection spectroscopy in thin monocrystalline plates of germanium

潘新宇, N.V.Chigarev, 龚旗煌   

  1. State Key Laboratory for Mesoscopic Physics and Department of Physics,Peking University, Beijing,100871, China
  • 收稿日期:2004-04-27 修回日期:2004-09-01 出版日期:2005-01-20 发布日期:2005-01-20
  • 基金资助:
    Project supported by the State Key Basic Research Special Foundation of China (Grant No TG1999075209), the National Natural Science Foundation of China ( Grant Nos 90206003,60378012, 10328407 and 90101027). The project was also supported by the Scientific

Femtosecond photodeflection spectroscopy in thin monocrystalline plates of germanium

Pan Xin-Yu (潘新宇), Chigarev N. V., Gong Qi-Huang (龚旗煌)   

  1. State Key Laboratory for Mesoscopic Physics and Department of Physics,Peking University, Beijing 100871, China
  • Received:2004-04-27 Revised:2004-09-01 Online:2005-01-20 Published:2005-01-20
  • Supported by:
    Project supported by the State Key Basic Research Special Foundation of China (Grant No TG1999075209), the National Natural Science Foundation of China ( Grant Nos 90206003,60378012, 10328407 and 90101027). The project was also supported by the Scientific

摘要: A highly sensitive photodeflection spectroscopy technique with femtosecond time resolution has been developed. Using this technique, we have measured accurately the shape of acoustic pulses, which were generated from the ultrafast phonon emission in a germanium plate. Supersonic expansion of photoexcited electron-hole plasma was observed. The characteristic velocity of plasma diffusion was evaluated. It exceeded the longitudinal sound velocity in germanium by a factor of 4.0.

关键词: ultrashort acoustic pulse, femtosecond laser pulse, photodeflection technique

Abstract: A highly sensitive photodeflection spectroscopy technique with femtosecond time resolution has been developed. Using this technique, we have measured accurately the shape of acoustic pulses, which were generated from the ultrafast phonon emission in a germanium plate. Supersonic expansion of photoexcited electron-hole plasma was observed. The characteristic velocity of plasma diffusion was evaluated. It exceeded the longitudinal sound velocity in germanium by a factor of 4.0.

Key words: ultrashort acoustic pulse, femtosecond laser pulse, photodeflection technique

中图分类号: 

  • 7847