Low offset frequency $1/f$ flicker noise in spin torque vortex oscillators
Abstract
Low frequency noise close to the carrier remains little explored in spin torque nano oscillators. However, it is crucial to investigate as it limits the oscillator's frequency stability. This work addresses the low offset frequency flicker noise of a TMR-based spin-torque vortex oscillator in the regime of large amplitude steady oscillations. We first phenomenologically expand the nonlinear auto-oscillator theory aiming to reveal the properties of this noise. We then present a thorough experimental study of the oscillator's flicker noise and discuss the results based on the theoretical predictions. Hereby, we connect the oscillator's nonlinear dynamics with the concept of flicker noise and furthermore refer to the influence of a standard noise description based on the Hooge formula, taking into account the non-constant magnetic oscillation volume, which contributes to the magnetoresistance.
Keywords
Cite
@article{arxiv.1906.10190,
title = {Low offset frequency $1/f$ flicker noise in spin torque vortex oscillators},
author = {Steffen Wittrock and Sumito Tsunegi and Kay Yakushiji and Akio Fukushima and Hitoshi Kubota and Paolo Bortolotti and Ursula Ebels and Shinji Yuasa and Gilles Cibiel and Serge Galliou and Enrico Rubiola and Vincent Cros},
journal= {arXiv preprint arXiv:1906.10190},
year = {2019}
}
Comments
10 pages