Influence of spin-flip on the performance of the spin-diode

TL;DR

This paper investigates how spin-flip processes affect the performance of a spin diode by analyzing current polarization and spin accumulation using a reduced density matrix approach, revealing conditions under which polarization diminishes.

Contribution

It provides analytical relations for current polarization and spin accumulation considering spin-flip effects, enhancing understanding of spin diode behavior under realistic conditions.

Findings

Current polarization drops to zero with fast spin-flip.

Spin accumulation decreases by up to 85% when spin-flip time equals tunneling time.

Current polarization varies with dot occupancy, increasing linearly in single occupancy.

Abstract

We study spin-dependent transport through a spin diode in the presence of spin-flip by means of reduced density matrix approach. The current polarization and the spin accumulation are computed and influence of spin-flip on the current polarization is also analyzed. Analytical relations for the current polarization and the spin accumulation are obtained as a function of polarization of ferromagnetic lead and the spin-flip rate. It is observed that the current polarization becomes zero under fast spin-flip and the spin accumulation decreases up to %85 when the time of spin-flip is equal to the tunneling time. It is also observed that the current polarization increases linearly when the dot is singly occupied, whereas its behavior is more complicated when the dot is doubly occupied.