Spin-dependent current noises in transport through coupled quantum dots

TL;DR

This paper investigates the spin-dependent current noise characteristics in coupled quantum dots connected to ferromagnetic electrodes, revealing complex behaviors influenced by spin polarization, Coulomb interaction, and tunneling effects.

Contribution

It introduces a particle-number-resolved master equation approach to analyze both total and spin-resolved current fluctuations in quantum dot systems.

Findings

Rich behaviors in self- and mutual-correlation functions of spin currents

Influence of spin polarization, Coulomb interaction, and tunneling on noise properties

Detailed analysis of spin-dependent current fluctuations

Abstract

Current fluctuations can provide additional insight into quantum transport in mesoscopic systems. The present work is carried out for the fluctuation properties of transport through a pair of coupled quantum dots which are connected with ferromagnetic electrodes. Based on an efficient particle-number-resolved master equation approach, we are concerned with not only fluctuations of the total charge and spin currents, but also of each individual spin-dependent component. As a result of competition among the spin polarization, Coulomb interaction, and dot-dot tunnel coupling, rich behaviors are found for the self- and mutual-correlation functions of the spin-dependent currents.