中国物理B ›› 2006, Vol. 15 ›› Issue (4): 822-827.doi: 10.1088/1009-1963/15/4/026

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Local density of states of dc-biased superlattices with time-dependent imperfection

阎维贤, 李向荣   

  1. Institute of Theoretical Physics and Department of Physics, Shanxi University, Taiyuan 030006, China
  • 收稿日期:2005-12-21 修回日期:2006-01-19 出版日期:2006-04-20 发布日期:2006-04-20
  • 基金资助:
    Project supported by the Natural Science Foundation of Shanxi Province (Grant No 20031006).

Local density of states of dc-biased superlattices with time-dependent imperfection

Yan Wei-Xian (阎维贤), Li Xiang-Rong (李向荣)   

  1. Institute of Theoretical Physics and Department of Physics, Shanxi University, Taiyuan 030006, China
  • Received:2005-12-21 Revised:2006-01-19 Online:2006-04-20 Published:2006-04-20
  • Supported by:
    Project supported by the Natural Science Foundation of Shanxi Province (Grant No 20031006).

摘要: The single-particle Green's function for a dc-biased superlattices with single impurity potential varying harmonically with time has been obtained in the framework of U(t,t') method and Floquet--Green's function. The calculation of the local density of states shows that new states will emerge between the resonant Wannier--Stark states as a result of the intervention of time-dependent impurity potential, and the increase in electric field strength of impurity will result in the growing of the number of new states between the gaps of neighbouring Stark ladders.

关键词: local density of states, Floquet-Green's function, defects and impurity

Abstract: The single-particle Green's function for a dc-biased superlattices with single impurity potential varying harmonically with time has been obtained in the framework of U(t,t') method and Floquet--Green's function. The calculation of the local density of states shows that new states will emerge between the resonant Wannier--Stark states as a result of the intervention of time-dependent impurity potential, and the increase in electric field strength of impurity will result in the growing of the number of new states between the gaps of neighbouring Stark ladders.

Key words: local density of states, Floquet-Green's function, defects and impurity

中图分类号:  (Semiconductor compounds)

  • 71.20.Nr
71.15.Ap (Basis sets (LCAO, plane-wave, APW, etc.) and related methodology (scattering methods, ASA, linearized methods, etc.)) 71.55.-i (Impurity and defect levels) 72.20.Ee (Mobility edges; hopping transport) 73.21.Cd (Superlattices)