Signature of symmetry of laterally coupled quantum dots in far-infrared spectrum  

作　　者：Gu Li-Ying Li Yan-Fang Chu Wei-Dong Wei Ying-Hui 谷利英;李艳芳;楚卫东;卫英慧(College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Institute of Applied Physics and Computational Mathematics,Beijing 100088,China)

机构地区：[1]College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China [2]Institute of Applied Physics and Computational Mathematics,Beijing 100088,China

出　　处：《Chinese Physics B》2012年第2期477-482,共6页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No.11074025);the National Basic Research Program of China (Grant No.2011CB922200);a grant from the China Academy of Engineering Physics

摘　　要：We study the effect of structure asymmetry on the energy spectrum and the far-infrared spectrum （FIR） of a lateral coupled quantum dot. The calculated spectrum shows that the parity break of coupled quantum dot results in more coherent superpositions in the low-lying states and exhibits unique anti-crossing in the two-electron FIR spectrum modulated by a magnetic field. We also find that the Coulomb correlation effect can make the FIR spectrum of coupled quantum dot without strict parity deviate greatly from Kohn theorem, which is just contrary to the symmetric case. Our results therefore suggest that FIR spectrum may be used to determine the symmetry of coupled quantum dot and to evaluate the degree of Coulomb interaction.We study the effect of structure asymmetry on the energy spectrum and the far-infrared spectrum （FIR） of a lateral coupled quantum dot. The calculated spectrum shows that the parity break of coupled quantum dot results in more coherent superpositions in the low-lying states and exhibits unique anti-crossing in the two-electron FIR spectrum modulated by a magnetic field. We also find that the Coulomb correlation effect can make the FIR spectrum of coupled quantum dot without strict parity deviate greatly from Kohn theorem, which is just contrary to the symmetric case. Our results therefore suggest that FIR spectrum may be used to determine the symmetry of coupled quantum dot and to evaluate the degree of Coulomb interaction.

关 键 词：structure symmetry far-infrared spectrum coupled quantum dot Coulomb interaction 

分 类 号：O488[理学—固体物理]