Quantum size effects on spin-tunneling time in a magnetic resonant tunneling diode

TL;DR

This paper theoretically investigates how quantum size effects influence spin-tunneling time and polarization in a magnetic resonant tunneling diode with a (Zn,Mn)Se layer, revealing oscillations and the impact of structural asymmetry.

Contribution

It introduces a detailed theoretical analysis of quantum size effects on spin-tunneling in magnetic RTDs, highlighting the role of layer thickness and asymmetry in device performance.

Findings

Spin-tunneling times oscillate with system parameters.

Structural asymmetry significantly affects tunneling time and spin polarization.

Proper layer thickness can enable high-speed, efficient spin-filter diodes.

Abstract

We study theoretically the quantum size effects of a magnetic resonant tunneling diode (RTD) with a (Zn,Mn)Se dilute magnetic semiconductor layer on the spin-tunneling time and the spin polarization of the electrons. The results show that the spin-tunneling times may oscillate and a great difference between the tunneling time of the electrons with opposite spin directions can be obtained depending on the system parameters. We also study the effect of structural asymmetry which is related to the difference in the thickness of the nonmagnetic layers. It is found that the structural asymmetry can greatly affect the traversal time and the spin polarization of the electrons tunneling through the magnetic RTD. The results indicate that, by choosing suitable values for the thickness of the layers, one can design a high speed and perfect spin-filter diode.