Ferromagnetic resonant tunneling diodes as spin polarimeters and polarizers

TL;DR

This paper proposes a method using ferromagnetic resonant tunneling diodes to accurately measure spin polarization and achieve high spin selectivity, aiding the study of magnetic semiconductor heterostructures.

Contribution

It introduces a novel technique based on differential conductance analysis for precise spin polarization measurement in ferromagnetic materials.

Findings

Accurate determination of ferromagnet spin polarization using resonant tunneling.

Achieving 100% spin selectivity under optimal conditions.

Potential application in studying magnetic semiconductor heterostructures.

Abstract

A method for measuring the degree of spin polarization of magnetic materials based on spin-dependent resonant tunneling is proposed. The device we consider is a ballistic double-barrier resonant structure consisting of a ferromagnetic layer embedded between two insulating barriers. A simple procedure, based on a detailed analysis of the differential conductance, allows to accurately determine the polarization of the ferromagnet. The spin-filtering character of such a system is furthermore addressed. We show that a 100% spin selectivity can be achieved under appropriate conditions. This approach is believed to be well suited for the investigation of diluted magnetic semiconductor heterostructures.