Role of the Non-Collinear Polarizer Layer in Spin Transfer Torque Switching Processes

TL;DR

This paper investigates how a non-collinear polarizer layer influences spin transfer torque switching, revealing it enhances spin dynamics coherence and affects switching current density depending on junction size and exchange stiffness.

Contribution

It demonstrates that a non-collinear polarizer layer improves the coherence of spin dynamics, providing a systematic understanding of switching current dependence beyond macro-spin models.

Findings

Non-collinear polarizer layer enhances spin dynamics coherence.

Switching current density depends systematically on junction size and exchange stiffness.

Breaking symmetric spin configurations improves switching behavior.

Abstract

We have recently reported that the spin transfer torque switching current density is very sensitive to not only the junction sizes but also the exchange stiffness constants of the free layer according to the micromagnetic simulations. The results are very complicate and far from the macro-spin model because of the non-coherent spin switching processes. The dependence of the switching current density on the junction sizes and the exchange stiffness constants becomes systematic when we employ the non-collinear polarizer layer. It is found that the non-collinear polarizer layer enhances the coherency of the spin dynamics by breaking symmetric spin configurations.