Amplitude-Phase Coupling in a Spin-Torque Nano-Oscillator

Abstract

The spin-torque nano-oscillator in the presence of thermal fluctuation is described by the normal form of the Hopf bifurcation with an additive white noise. By the application of the reduction method, the amplitude-phase coupling factor, which has a significant effect on the power spectrum of the spin-torque nano-oscillator, is calculated from the Landau-Lifshitz-Gilbert-Slonczewski equation with the nonlinear Gilbert damping. The amplitude-phase coupling factor exhibits a large variation depending on in-plane anisotropy under the practical external fields.

4 pages, 4 figures, submitted to Journal of Applied Physics via MMM 2008

References in corpus (7)

• Microwave Oscillations of a Nanomagnet Driven by a Spin-Polarized Current
• Direct-Current Induced Dynamics in Co90Fe10/Ni80Fe20 Point Contacts
• Generation linewidth of an auto-oscillator with a nonlinear frequency shift: Spin-torque nano-oscillator
• Current-driven microwave oscillations in current perpendicular-to-plane spin-valve nanopillars
• Lineshape distortion in a nonlinear auto-oscillator near generation threshold: Application to spin-torque nano-oscillators
• Microwave power generated by a spin-torque oscillator in the presence of noise
• Stochastic theory of spin-transfer oscillator linewidths

Cited by in corpus (8)

• Experimental evidence of self-localized and propagating spin wave modes in obliquely magnetized current-driven nanocontacts
• Non-white frequency noise in spin torque oscillators and its effect on spectral linewidth
• Measurement of nonlinear frequency shift coefficient in spin-torque oscillators based on MgO tunnel junctions
• Large amplitude microwave emission and reduced nonlinear phase noise in Co2Fe(Ge0.5Ga0.5) Heusler alloy based pseudo spin valve nanopillars
• Low offset frequency $1/f$ flicker noise in spin torque vortex oscillators
• A quasi-linear spin-torque nano-oscillator via enhanced negative feedback of power fluctuations
• Layer-selective detection of magnetization directions from two layers of antiferromagnetically-coupled magnetizations by ferromagnetic resonance using a spin-torque oscillator
• Low-non-linearity spin-torque oscillations driven by ferromagnetic nanocontacts