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arXiv · 1308.3264

Spin-orbit interaction induced singularity of the charge density relaxation propagator

S. M. Badalyan·A. Matos-Abiague·J. Fabian·G. Vignale·F. M. Peeters
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Abstract

The charge density relaxation propagator of a two dimensional electron system, which is the slope of the imaginary part of the polarization function, exhibits singularities for bosonic momenta having the order of the spin-orbit momentum and depending on the momentum orientation. We have provided an intuitive understanding for this non-analytic behavior in terms of the inter chirality subband electronic transitions, induced by the combined action of Bychkov-Rashba (BR) and Dresselhaus (D) spin-orbit coupling. It is shown that the regular behavior of the relaxation propagator is recovered in the presence of only one BR or D spin-orbit field or for spin-orbit interaction with equal BR and D coupling strengths. This creates a new possibility to influence carrier relaxation properties by means of an applied electric field.

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S. M. Badalyan, A. Matos-Abiague, J. Fabian, G. Vignale, F. M. Peeters. 2013-08-19. Spin-orbit interaction induced singularity of the charge density relaxation propagator. https://doi.org/10.1103/physrevb.88.195402

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