57Fe and 61Ni NMR in intercrystalline boundaries of permalloy films

NMR is investigated on 57Fe and 61Ni nuclei in permalloy films deposited on the substrate at room temperature. Essential expansion of resonance line from the side of low frequencies is revealed by resonance of iron and nickel nuclei being in grain boundaries of the film. An experiment on vacuum heat treatment of specially prepared samples comprising two layers of permalloy between which iron layer enriched by 57Fe isotope has been placed is conducted to test the given supposition. The effect of heat treatment on NMR spectra of the samples is studied. The Moessbauer effect has been used as a control method. As a result, it is stated that mean value of the local field on 57Fe nuclei in grain boundaries of the permalloy film makes up 198x103 A/cm, and it makes up 53x103 A/cm on 61Ni nuclei. Mean value of magnetization of intergrain boundary substance is estimated according to these data. It is obtained that Msub(b) is approximately equal to 0.5 M