Kondo transport in an anisotropic two-dimensional electron gas with quadratic momentum-dependent spin splitting

Abstract

We investigate the transport properties of an anisotropic two-dimensional electron gas with a quadratic spin texture, described by a low-energy effective $k\cdot p$ model, in the presence of $S=1/2$ Kondo impurities. We develop a Green's function framework that captures the interplay between the spin texture and the Kondo scattering for calculating transport properties in such systems. Using this framework together with numerical renormalization group (NRG) calculations, we evaluate the longitudinal resistivity components ${\rho }^{xx}(T)$ and ${\rho }^{yy}(T)$ and analyze their temperature dependence. We further determine the Kondo temperature $T_K(\alpha )$ and the impurity screening function $p(\alpha )$ and demonstrate that they decrease strongly with increasing quadratic spin-splitting coupling $\alpha$.

18 pages, 7 figures; v3: substantially rewritten, with a stronger version of the main result