Spin filter of electrons through a zeeman splitting single quantum dot

TL;DR

This paper investigates how Zeeman splitting in a quantum dot can be used to create a spin filter, analyzing the effects of Coulomb blockade and deriving conditions for high-quality spin polarization.

Contribution

It provides an analytical framework for understanding spin filtering in quantum dots considering Coulomb blockade and Zeeman effects, with explicit relations for optimal conditions.

Findings

Transport windows for different polarization states are identified.

Analytical solutions for system behavior are derived.

Conditions for high-quality spin filtering are established.

Abstract

Electron spin filter induced by Zeeman splitting in a few-electron quantum dot coupled to two normal electrodes is studied considering Coulomb blockade effect. Based on the Anderson model and Liouville-von Neumann equation, equation of motion of the system is derived and analytical solutions are achieved. Transport windows for perfectly polarized current, partially polarized current and non-polarized current induced by the Zeeman splitting energy and Coulomb blockade potential are exploited. We will give the relations of voltage, magnetic field and temperature for high quality spin filtering.