Zero-field dynamics stabilized by in-plane shape anisotropy in MgO-based spin-torque oscillators
Materials Science
2019-07-03 v1 Mesoscale and Nanoscale Physics
Abstract
Here we demonstrate numerically that shape anisotropy in MgO-based spin-torque nano-oscillators consisting of an out-of-plane magnetized free layer and an in-plane polarizer is necessary to stabilize out-of-plane magnetization precession without the need of external magnetic fields. As the in-plane anisotropy is increased, a gradual tilting of the magnetization towards the in-plane easy direction is introduced, favouring zero-field dynamics over static in-plane states. Above a critical value, zero-field dynamics are no longer observed. The optimum ratio of in-plane shape to out-of-plane uniaxial anisotropy, for which large angle out-of-plane zero-field dynamics occur within the widest current range, is reported.
Keywords
Cite
@article{arxiv.1811.00106,
title = {Zero-field dynamics stabilized by in-plane shape anisotropy in MgO-based spin-torque oscillators},
author = {Ewa Kowalska and Attila Kákay and Ciarán Fowley and Volker Sluka and Jürgen Lindner and Jürgen Fassbender and Alina M. Deac},
journal= {arXiv preprint arXiv:1811.00106},
year = {2019}
}