Shot noise and linear conductance in a transport through quantum dot coupled to polarized leads

Abstract

We study the influence of polarized leads and of magnetic field on the noise power and on transport through a link which may be a quantum dot or a point junction. We suggest that such link is tuned to the local spin regime and reveals Kondo type behavior. The implication of superconductivity is also analyzed in the case when one of the leads is a superconductor. Specifically, we calculate the noise power to the third order in the Kondo coupling. With the help of fluctuation‐dissipation theorem we can further define the linear conductance as a function of the polarization and magnetic field. For dot spin operators we used their representation in terms of mixed Dirac and Majorana fermions. The important output of the derivation with both, spin polarization and magnetic field included, is the potential scattering contribution which acquires logarithmic dependence on the band width. Motivated by experiment [1] we analyze a set configuration when only one lead is polarized. The Kondo temperature is defined wit...