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arXiv · 1003.2433

Spin-orbit excitations of quantum wells

A. Ambrosetti·J. M Escartin·E. Lipparini·F. Pederiva
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Abstract

Confinement asymmetry effects on the photoabsorption of a quantum well are discussed by means of a sum-rules approach using a Hamiltonian including a Rashba spin-orbt coupling. We show that while the strength of the excitation is zero when the spin-orbit coupling is neglected, the inclusion of the spin-orbit interaction gives rise to a non zero strength and mean excitation energy in the far-infrared region. A simple expression for these quantities up to the second order in the Rashba parameter was derived. The effect of two-body Coulomb interaction is then studied by means of a Quantum Monte Carlo calculation, showing that electron-electron correlations induce only a small deviation from the independent particle model result.

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A. Ambrosetti, J. M Escartin, E. Lipparini, F. Pederiva. 2010-03-11. Spin-orbit excitations of quantum wells. https://doi.org/10.1209/0295-5075%2F94%2F27004

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