Spin relaxation and the Kondo effect in transition metal dichalcogenide monolayers

TL;DR

This paper explores how magnetic impurities affect spin relaxation and Kondo resistivity in doped transition metal dichalcogenide monolayers, revealing unique behaviors due to spin-orbit effects and intervalley scattering.

Contribution

It provides a detailed analysis of spin relaxation times and Kondo temperature dependence in TMD monolayers, highlighting differences from conventional metals and other Dirac materials.

Findings

Longer momentum and spin relaxation times inside the spin split valence band region.

Weak dependence of Kondo temperature on doping despite spin-orbit splitting.

Conductivity decreases near the Kondo temperature, varying with doping.

Abstract

We investigate the spin relaxation and Kondo resistivity caused by magnetic impurities in doped transition metal dichalcogenides monolayers. We show that momentum and spin relaxation times due to the exchange interaction by magnetic impurities, are much longer when the Fermi level is inside the spin split region of the valence band. In contrast to the spin relaxation, we find that the dependence of Kondo temperature $T_K$ on the doping is not strongly affected by the spin-orbit induced splitting, although only one of the spin species are present at each valley. This result, which is obtained using both perturbation theory and poor man's scaling methods, originates from the intervalley spin-flip scattering in the spin-split region. We further demonstrate the decline in the conductivity with temperatures close to $T_K$ which can vary with the doping. Our findings reveal the qualitative difference with the Kondo physics in conventional metallic systems and other Dirac materials.