| Popis: |
We derive and analyze the relaxation frequency ν of exciton in a quantum well using the self-consistent Green's function method. The exciton relaxation is caused by the individual electron and hole scattering from the randomly-rough well interface. We reveal two types of ground-state exciton resonance and obtain the criteria for the transition from the asymmetric (sharp) resonance to the symmetric (broad) one. The dependence of the excitron–surface relaxation on the microscopic parameters of the interface defects, the average well width d and on the exciton characteristics is analyzed analytically. Specifically, in the case of sharp resonance the frequency ν ∝ d −6 , whereas for broad resonance ν ∝ d −3 . Moreover, ν is proportional to the ratio of the total exciton mass M over the squared reduced mass μ 2 ( ν ∝ M / μ 2 ). |
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