Tuning of Single Sideband Generation by In-Plane Field Angle in Spin Torque Nano-Oscillators

We report on a macrospin simulation study of field angle dependent single sideband (SSB) generation in a spin-torque nano- oscillator with free layer magnetized in the film plane. We show that the single sideband generation during analog modulation of spin torque nano-oscillator depends strongly on the in-plane field angle. We validate our results by using non-linear frequency and amplitude modulation theory which describes the angular dependence of single sideband generation by taking into account of the angular dependence of the nonlinear frequency and amplitude modulation sensitivity coefficients. We propose an optimum range of in-plane field angle for the SSB generation.