Metastable state in a shape-anisotropic single-domain nanomagnet subjected to spin-transfer-torque

TL;DR

This paper predicts a new metastable magnetization state in a shape-anisotropic nanomagnet caused by spin-transfer-torque, which impacts the stability and switching behavior relevant for magnetic memory devices.

Contribution

It introduces the concept of a metastable state induced by spin-transfer-torque in a single-domain nanomagnet with uniaxial shape anisotropy, highlighting its technological significance.

Findings

Metastable state exists under certain current conditions.

Above a threshold current, the metastable state disappears.

Implications for spin-transfer-torque magnetic memory.

Abstract

We predict the existence of a new metastable magnetization state in a single-domain nanomagnet with uniaxial shape anisotropy. It emerges when a spin-polarized current, delivering a spin-transfer-torque, is injected into the nanomagnet. It can trap the magnetization vector and prevent spin-transfer-torque from switching the magnetization from one stable state along the easy axis to the other. Above a certain threshold current, the metastable state no longer appears. This has important technological consequences for spin-transfer-torque based magnetic memory and logic systems.