AN INVESTIGATION OF THE ELECTRODEPOSITED INHOMOGENEOUS ALLOYED FILM CU0.94CO0.06 BY MEANS OF SQUID MAGNETOMETRY

The magnetic behaviour of the inhomogeneous alloyed him, Cu0.94Co0.06, produced by electrodeposition has been investigated in the temperatur e range 2 to 300 K and in magnetic fields of up to 5 T using SQUID mag netometry, The films exhibit either hysteretic or reversible behaviour depending upon the temperature. This is interpreted as being due to t he presence of small, Fee, Go-rich particles of Fee Co in the non-magn etic matrix, giving rise to superparamagnetism at higher temperatures. With the help of low-field susceptibility measurements made on sample s cooled in zero field we have been able to determine the distribution of blocking temperatures and thus make an estimate of the size distri bution of the particles in the Cu matrix; these have been found to ran ge in diameter from 6 to 12 nm. These results have been compared with values obtained from a measurement of the temperature dependence of th e remanence. We have found that, even in such a relatively dilute magn etic system as Cu0.94Co0.06, interactions between magnetic clusters ar e not negligible. The interaction energy is estimated to be of the ord er of 1.7 x 10(-3) eV.