Enhancement of Spin-transfer torque switching via resonant tunneling

TL;DR

This paper introduces a resonant tunneling magnetic tunnel junction design that significantly improves spin-transfer torque switching efficiency, reducing switching voltages and enhancing magnetoresistance compared to traditional devices.

Contribution

It presents a novel device structure utilizing resonant tunneling in MgO-semiconductor heterostructures to enhance spin-transfer torque switching, with detailed theoretical modeling and design proposals.

Findings

Reduced switching voltage by up to 44%

Enhanced tunnel magneto-resistance characteristics

Potential for practical device applications

Abstract

We propose the use of resonant tunneling as a route to enhance the spin-transfer torque switching characteristics of magnetic tunnel junctions. The proposed device structure is a resonant tunneling magnetic tunnel junction based on a MgO-semiconductor heterostructure sandwiched between a fixed magnet and a free magnet. Using the non-equilibrium Green's function formalism coupled self consistently with the Landau-Lifshitz-Gilbert-Slonczewski equation, we demonstrate enhanced tunnel magneto-resistance characteristics as well as lower switching voltages in comparison with traditional trilayer devices. Two device designs based on MgO based heterostructures are presented, where the physics of resonant tunneling leads to an enhanced spin transfer torque thereby reducing the critical switching voltage by up to 44%. It is envisioned that the proof-of-concept presented here may lead to practical device designs via rigorous materials and interface studies.