Ac Susceptibility Measurement Using a Vibrating Sample Magnetometer

We propose the addition of an ac susceptibility measurement capability to the vibrating sample magnetometry (VSM) method. By applying an ac magnetic field to the vibrating sample, asymmetric sidebands appear at the mixed VSM and ac frequencies. We analyze these sidebands to obtain the complex ac susceptibility, simultaneously with the dc magnetization of the VSM method. We verify our method on a permalloy thin film sample.