CORRELATIONS BETWEEN FERROMAGNETIC-RESONANCE LINEWIDTHS AND SAMPLE QUALITY IN THE STUDY OF METALLIC ULTRATHIN FILMS

Ferromagnetic resonance is commonly used in the study of thin ferromag netic films, In past investigations, most attention has been concentra ted on the resonance field H-r, with relatively little consideration f or the information contained in the peak-to-peak linewidth Delta H-pp. In this paper we focus specifically on Delta H-pp, looking at a varie ty of Fe, Co, Ni, and Gd films (thickness <20 monolayers) epitaxially proven on different single-crystal substrates of various orientations, as well as an Fe-4/V-4(100) multilayer. We identify common features i n the linewidths which correlate with other film properties, such as i ntrinsic spin-damping mechanisms, and the structural and magnetic qual ity. The dependence of Delta H-pp on film thickness and annealing cond itions, as well as temperature, frequency, and magnetic-field orientat ion is examined. Particularly interesting is an angular dependence of Delta H-pp, seen most clearly in Fe-4/V-4 which is related to:the crys tallographic axes and appears to be correlated with the intrinsic damp ing of the spins.