中国物理B ›› 2000, Vol. 9 ›› Issue (11): 813-823.doi: 10.1088/1009-1963/9/11/004

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THEORY OF INTERBAND COHERENCE AND INVERSIONLESS BISTABILITY IN SEMICONDUCTOR LASERS

葛国勤, 梁培   

  1. Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
  • 收稿日期:2000-04-13 修回日期:2000-07-15 出版日期:2000-11-15 发布日期:2005-06-10
  • 基金资助:
    Project supported by the Hong Kong Research Grants Council (Grant No. CUHK 4282/00P), the National Natural Science Foundation of China(Grant No. 69688004), GGQ is also supported by the Visiting Scholar Foundation of Key Laboratory of Laser Technology, Hua

THEORY OF INTERBAND COHERENCE AND INVERSIONLESS BISTABILITY IN SEMICONDUCTOR LASERS

Ge Guo-qin (葛国勤), Leung Pui Tang (梁培)   

  1. Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
  • Received:2000-04-13 Revised:2000-07-15 Online:2000-11-15 Published:2005-06-10
  • Supported by:
    Project supported by the Hong Kong Research Grants Council (Grant No. CUHK 4282/00P), the National Natural Science Foundation of China(Grant No. 69688004), GGQ is also supported by the Visiting Scholar Foundation of Key Laboratory of Laser Technology, Hua

摘要: Coherent transitions of charge carriers between the conduction and valence bands of a semiconductor medium are essential for the operation of a semiconductor laser. In this paper, we study how such interband coherence can be set up by an injection current and a coherent pump-field. In the absence of the pump-field, the injection current is the only source to establish the interband coherence in a semiconductor laser system. A laser threshold is obtained, which shows that a strongly coupled high-Q microcavity has a low threshold value. However, when an external pump-field serving as another mechanism to create the interband coherence is applied, the threshold value of the injection current can be lowered and it vanishes for sufficiently strong field. Besides, if the pump-field exceeds a threshold value, it is even possible to achieve a bistability in the inversionless region. Some fundamental macroscopic properties, including polarization, absorption and dispersion for the semicoductor system, are also obtained analytically.

Abstract: Coherent transitions of charge carriers between the conduction and valence bands of a semiconductor medium are essential for the operation of a semiconductor laser. In this paper, we study how such interband coherence can be set up by an injection current and a coherent pump-field. In the absence of the pump-field, the injection current is the only source to establish the interband coherence in a semiconductor laser system. A laser threshold is obtained, which shows that a strongly coupled high-Q microcavity has a low threshold value. However, when an external pump-field serving as another mechanism to create the interband coherence is applied, the threshold value of the injection current can be lowered and it vanishes for sufficiently strong field. Besides, if the pump-field exceeds a threshold value, it is even possible to achieve a bistability in the inversionless region. Some fundamental macroscopic properties, including polarization, absorption and dispersion for the semicoductor system, are also obtained analytically.

Key words: interband coherence, inversionless bistability, semiconductor laser

中图分类号:  (Semiconductor lasers; laser diodes)

  • 42.55.Px
42.60.Da (Resonators, cavities, amplifiers, arrays, and rings) 42.60.Jf (Beam characteristics: profile, intensity, and power; spatial pattern formation) 42.60.Lh (Efficiency, stability, gain, and other operational parameters) 42.65.Pc (Optical bistability, multistability, and switching, including local field effects)