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arXiv · 0908.3104

Fine structure of two-electron states in single and double quantum dots

M. M. Glazov
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Abstract

Energy spectrum fine structure of triplet two-electron states is investigated theoretically. Spin-orbit interaction induced terms in the effective Hamiltonian of electron-electron interaction are derived for zinc-blende lattice semiconductor nanostructures: quantum wells and quantum dots. The effects of bulk and structural inversion asymmetry are taken into account. Simple analytical expressions describing the splittings of the two-electron states localized in a single quantum dot and in a lateral double quantum dot are derived. The spin degeneracy of triplet states is shown to be completely lifted by the spin-orbit interaction. An interplay of the conduction band spin splitting and the spin-orbit terms in electron-electron interaction is discussed. The photoluminescence spectra of hot trions and of doubly charged excitons are calculated and are shown to reveal the fine structure of two-electron states.

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M. M. Glazov. 2009-08-22. Fine structure of two-electron states in single and double quantum dots. https://doi.org/10.1088/0953-8984%2F22%2F2%2F025301

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