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arXiv · cond-mat/0403545

Elementary electronic excitation from a two-dimensional hole gas in the presence of spin-orbit interaction

Abstract

We present a theoretical study of the elementary electronic excitation associated with plasmon modes in a two-dimensional hole gas (2DHG) in the presence of spin-orbit (SO) interaction induced by the Rashba effect. The calculation is carried out using a standard random-phase-approximation approach. It is found that in such a spintronic system, plasmon excitation can be achieved via intra- and inter-SO electronic transitions around the Fermi level. As a result, the intra- and inter-SO plasmon modes can be observed. More importantly, the plasmon modes induced by inter-SO transition are optic-like and these modes can be directly applied to identify the Rashba spin splitting in 2DHG systems through optical measurements. The interesting features of the plasmon excitation in a spin split 2DHG are analyzed and discussed in details. Moreover, the results obtained for a 2DHG are compared with those obtained for a spin-splitting 2DEG reported very recently.

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W. Xu, L. B. Lin. 2004-03-21. Elementary electronic excitation from a two-dimensional hole gas in the presence of spin-orbit interaction. https://doi.org/10.1088/0953-8984%2F16%2F10%2F010

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