Transport through a double quantum dot system with non-collinearly polarized leads

We investigate linear and non-linear transport in a double quantum dot system weakly coupled to spin-polarized leads. In the linear regime, the conductance as well as the non-equilibrium spin accumulation are evaluated in analytic form. The conductance as a function of the gate voltage exhibits four...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2008-07
Main Authors: Hornberger, Ralph Peter, Koller, Sonja, Begemann, Georg, Donarini, Andrea, Grifoni, Milena
Format: Article
Language:English
Subjects:
Dependence
Electric potential
Holes (electron deficiencies)
Quantum dots
Resistance
Symmetry
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We investigate linear and non-linear transport in a double quantum dot system weakly coupled to spin-polarized leads. In the linear regime, the conductance as well as the non-equilibrium spin accumulation are evaluated in analytic form. The conductance as a function of the gate voltage exhibits four peaks of different height, with mirror symmetry with respect to the charge neutrality point. As the polarization angle is varied, the position and shape of the peaks changes in a characteristic way which preserves the electron-hole symmetry of the problem. In the nonlinear regime negative differential conductance features occur for non collinear magnetisations of the leads. In the considered sequential tunneling limit, the tunneling magneto resistance (TMR) is always positive with a characteristic gate voltage dependence for non-collinear magnetization. If a magnetic field is added to the system, the TMR can become negative.
ISSN:2331-8422
DOI:10.48550/arxiv.0712.0757