Non-equilibrium transport through quantum dots with Dzyaloshinsky--Moriya--Kondo interaction

TL;DR

This paper investigates how a Dzyaloshinsky--Moriya--Kondo interaction affects non-equilibrium transport in a quantum dot, revealing voltage-dependent magnetic fields and conductance asymmetries through renormalization effects.

Contribution

It introduces the impact of DMK interaction on quantum dot transport and demonstrates its strong renormalization and observable signatures at low temperatures.

Findings

Renormalization of DMK interaction at low temperatures

Voltage dependence of the effective magnetic field

Asymmetric differential conductance with logarithmic enhancements

Abstract

We study non-equilibrium transport through a single-orbital Anderson model in a magnetic field with spin-dependent hopping amplitudes. In the cotunneling regime it is described by an effective spin-1/2 dot with a Dzyaloshinsky--Moriya--Kondo (DMK) interaction between the spin on the dot and the electron spins in the leads. Using a real-time renormalization group technique we show that at low temperatures (i) the DMK interaction is strongly renormalized, (ii) the renormalized magnetic field acquires a linear voltage dependence, and (iii) the differential conductance exhibits a voltage asymmetry which is strongly enhanced by logarithmic corrections. We propose transport measurements in which these signatures can be observed.