High power radio frequency oscillation by spin transfer torque in a Co2MnSi layer: Experiment and macrospin simulation

Abstract

We experimentally and numerically investigated rf oscillation induced by spin transfer torque in a current-perpendicular-to-plane giant magnetoresistance (GMR) device with full-Heusler Co2MnSi (CMS) layers. High output power (Prf) of 1 nW was experimentally achieved owing to the large GMR effect resulting from the half-metallic feature of the CMS layers. However, the high power rf oscillation was observed only in the narrow dc current (Idc) region. Macrospin simulation suggested that the high spin polarization of CMS layers led to narrowing the optimum Idc region for the rf oscillation.