Effect of Spin-Torque on Thermal Mag-Noise in a TMR Read Head

概要

論文の詳細を見る
This paper describes the noise spectra in the GHz range of tunneling magnetoresistive (TMR) read heads as a function of both bias current and external magnetic field in order to understand the effect of spin-torque (ST) on the thermally excited magnetization fluctuation noise (thermal mag-noise) in the TMR heads. A strong noise spectral peak at around 3-4 GHz is either enhanced or reduced depending on both the bias current and the external magnetic field. This result demonstrates that the ST influences the thermal mag-noise originated from the free layer under the positive (or negative) bias current in case the magnetization of the free and reference layers are nearly anti-parallel (or parallel) to each other.