a Institute of Theoretical Physics, Shanxi University, Taiyuan 030006, China; b Institute of Physics and Center for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, China; c Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
Abstract The eigenstates and eigenspectrum of a charged particle in a one-dimensional semiconductor superlattice with an impurity under the action of a dc electric field are investigated employing the single-band tight-binding model. We find that the system undergoes a series of avoided crossings, at which resonant oscillations between the impurity and its nearest neighbour occur if appropriate conditions are met, suggesting an effective two-level approximation. This phenomenon shows that introducing an impurity in a perfect lattice provides a promising structure for the observation of terahertz radiation.
Received: 15 December 2000
Accepted manuscript online:
Fund: Project supported by the National Natural Science Foundation of China (Grant No. 19725417), by National "Climb" Program of China (Grant No. 95-YU-41), and by a Grant of the China Academy of Engineering and Physics.
Cite this article:
Zhang Ai-zhen (张爱珍), Zhang Ping (张平), Duan Su-qing (段素青), Zhao Xian-geng (赵宪庚), Liang Jiu-qing (梁九卿) AN EFFECTIVE TWO-LEVEL CHANNEL FOR AN IMPURITY IN A SUPERLATTICE 2001 Chinese Physics 10 537
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