A Study on the Phase Noise Performance of Coupled Spin Torque Oscillators

Spin transfer torque driven oscillation (STO) in magnetic tunnel junction (MTJ) device can be an attractive solution for microwave signal generation with large frequency tunability, low power consumption and small footprint. In this paper, study shows that single such STO device cannot achieve noise performance in the range suitable for RF applications. Various coupling mechanisms are explored to show that by coupling more than two oscillators globally (all reciprocal), a significant improvement in phase noise is possible. The effect of the coupling strength and the increasing number of coupled oscillators on the phase noise performance is also evaluated.