Mahdi Zarea, Sergio E. Ulloa, Nancy Sandler
We analyze the physics of a one-orbital Anderson impurity model in a
two-dimensional electron gas in the presence of Rashba spin-orbit (RSO)
interactions in the Kondo regime. The spin SU(2) symmetry breaking results in
an effective two-band electron gas coupled to the impurity. The Kondo regime is
obtained by a Schrieffer-Wolff transformation revealing the existence of a
parity breaking term with the form of the Dzyaloshinsky-Moriya (DM)
interaction. The DM term vanishes at the particle-hole symmetric point of the
system, but it has important effects otherwise. Performing a renormalization
group (RG) analysis we find that the model describes a two-channel Kondo system
with ferro- and anti-ferromagnetic couplings. Furthermore, the DM term
renormalizes the antiferromagnetic Kondo coupling producing an exponential
enhancement of the Kondo temperature. We suggest that these effects can be
observed in semiconducting systems, as well as in graphene and topological
insulators.
View original:
http://arxiv.org/abs/1105.3522
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