rf auto-oscillation induced by spin-transfer torque was investigated in Fe/Cr/Fe systems that had antiferromagnetically coupled Fe layers. As the coupling strength increased, the generation linewidth (Δf) reduced remarkably whereas the oscillation frequency (f) and the onset current of the auto-oscillation increased. The strong antiferromagnetic coupling led to less variation in f depending on the bias current. These results indicate that the antiferromagnetic coupling allows us to reduce Δf and to control the nonlinearity of the rf auto-oscillation.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)