Line shape distortion in a nonlinear auto-oscillator near generation threshold: application to spin-torque nano-oscillators.
The power spectrum of an auto-oscillator with a large frequency nonlinearity in a noisy environment is calculated. The power spectrum becomes strongly non-Lorentzian, broadened, and asymmetric near the generation threshold. A Lorentzian spectrum is recovered far below and far above the threshold, which suggests that line shape distortions provide a signature of the threshold. We show that the developed theory adequately describes the observed behavior of a strongly nonlinear spin-torque nano-oscillator.
Institut d'Electronique Fondamentale, UMR CNRS 8622, Université Paris-Sud, 91405 Orsay, France. joo.von.kim@u-psud.fr
Joo-Von
JV
Kim
Q
Q
Mistral
C
C
Chappert
V S
VS
Tiberkevich
A N
AN
Slavin