Spin-torque oscillator based on tilted magnetization of the fixed layer

TL;DR

This paper investigates a spin-torque oscillator with a tilted fixed layer magnetization, demonstrating its ability to generate strong microwave signals without external magnetic fields through numerical simulations.

Contribution

It introduces a novel STO design with tilted fixed layer magnetization and analyzes its microwave generation capabilities using macro-spin simulations.

Findings

Strong microwave signals can be generated at zero magnetic field.

Tilt angles significantly influence the microwave output.

Material choice like L10 FePt enables the tilt magnetization.

Abstract

The spin torque oscillator (STO), where the magnetization of the fixed layer is tilted out of the film plane, is capable of strong microwave signal generation in zero magnetic field. Through numerical simulations of the Landau-Lifshitz-Gilbert-Slonczewski equations, within a macro-spin approximation, we study the microwave signal generation as a function of drive current for two realistic tilt angles. The tilt magnetization of the fixed layer can be achieved by using a material with high out-of-plane magnetocrystalline anisotropy, such as L10 FePt.