THEORY OF MAGNETIC DISSIPATION IMAGING

A model is presented for magnetic dissipation imaging and magnetic for ce gradient imaging obtained with a vibrating ferromagnetic tip and a ferromagnetic thin film sample. Results of calculations are compared t o recent experiments and show good agreement using known bulk values f or the magnetic parameters of tip and sample. We suggest that oscillat ions of domain wall width result in magnetoelastic emission of phonons . These phonons carry energy from the tig, leading to image contrast a t domain walls. We also discuss the energy dissipation resulting from eddy current losses in the tip and sample. (C) 1997 American Institute of Physics.