Bistability in a magnetic and nonmagnetic double-quantum-well structure mediated by the magnetic phase transition

TL;DR

This paper explores how hole redistribution in a magnetic and nonmagnetic double quantum well structure can induce bistability through a magnetic phase transition, potentially enabling stable, scalable memory devices.

Contribution

It introduces a model showing bistability driven by hole redistribution mediated by magnetic phase transition in a double quantum well structure.

Findings

Bistability occurs via hole redistribution affecting magnetic properties.

A large parameter space supports bistability in the system.

Potential for stable, scalable memory applications.

Abstract

The hole distribution in a double quantum well (QW) structure consisting of a magnetic and a nonmagnetic semiconductor QW is investigated as a function of temperature, the energy shift between the QWs, and other relevant parameters. When the itinerant holes mediate the ferromagnetic ordering, it is shown that a bistable state can be formed through hole redistribution, resulting in a significant change in the properties of the constituting magnetic QW (i.e., the paramagnetic-ferromagnetic transition). The model calculation also indicates a large window in the system parameter space where the bistability is possible. Hence, this structure could form the basis of a stable memory element that may be scaled down to a few hole regime.