Time and frequency domain measurements of ferromagnetic resonance in small spin-valve

Time and frequency domain magnetoresistance measurements of ferromagnetic resonance (FMR) in small spin-valve devices are presented along with comparisons to single-domain simulations. The measurements and simulations give consistent results for rotational motion with angular deviations of less than 30/spl deg/ from the easy axis. While the time and frequency domain measurements produce similar results fur ideal devices in the linear regime, each technique provides different information as the devices become nonlinear and less ideal. Both time and frequency domain magnetoresistance measurements allow the study of FMR in considerably smaller magnetic structures than can be done with conventional techniques.