中国物理B ›› 2007, Vol. 16 ›› Issue (1): 67-71.doi: 10.1088/1009-1963/16/1/012

• ATOMIC AND MOLECULAR PHYSICS • 上一篇    下一篇

Lifetime of resonant state in a spherical quantum dot

李春雷, 肖景林   

  1. College of Physics and Electromechanics, Inner Mongolia National University,Tongliao 028043, China
  • 收稿日期:2006-01-24 修回日期:2006-07-10 出版日期:2007-02-01 发布日期:2007-02-01
  • 基金资助:
    Project supported by the National Nature Science Foundation of China (Grant No~10347004).

Lifetime of resonant state in a spherical quantum dot

Li Chun-Lei(李春雷) and Xiao Jing-Lin(肖景林)   

  1. College of Physics and Electromechanics, Inner Mongolia National University,Tongliao 028043, China
  • Received:2006-01-24 Revised:2006-07-10 Online:2007-02-01 Published:2007-02-01
  • Supported by:
    Project supported by the National Nature Science Foundation of China (Grant No~10347004).

摘要: This paper calculates the lifetime of resonant state and transmission probability of a single electron tunnelling in a spherical quantum dot (SQD) structure by using the transfer matrix technique. In the SQD, the electron is confined both transversally and longitudinally, the motion in the transverse and longitudinal directions is separated by using the adiabatic approximation theory. Meanwhile, the energy levels of the former are considered as the effective confining potential. The numerical calculations are carried out for the SQD consisting of GaAs/InAs material. The obtained results show that the bigger radius of the quantum dot not only leads significantly to the shifts of resonant peaks toward the low-energy region, but also causes the lengthening of the lifetime of resonant state. The lifetime of resonant state can be calculated from the uncertainty principle between the energy half width and lifetime.

Abstract: This paper calculates the lifetime of resonant state and transmission probability of a single electron tunnelling in a spherical quantum dot (SQD) structure by using the transfer matrix technique. In the SQD, the electron is confined both transversally and longitudinally, the motion in the transverse and longitudinal directions is separated by using the adiabatic approximation theory. Meanwhile, the energy levels of the former are considered as the effective confining potential. The numerical calculations are carried out for the SQD consisting of GaAs/InAs material. The obtained results show that the bigger radius of the quantum dot not only leads significantly to the shifts of resonant peaks toward the low-energy region, but also causes the lengthening of the lifetime of resonant state. The lifetime of resonant state can be calculated from the uncertainty principle between the energy half width and lifetime.

Key words: spherical quantum dot, lifetime of resonant state, transmission probability

中图分类号:  (Coulomb blockade; single-electron tunneling)

  • 73.23.Hk
71.15.Ap (Basis sets (LCAO, plane-wave, APW, etc.) and related methodology (scattering methods, ASA, linearized methods, etc.)) 71.20.Nr (Semiconductor compounds) 73.21.La (Quantum dots) 73.63.Kv (Quantum dots)