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 temperature range 2 to 300 K and in magnetic fields of up to 5 T using SQUID magnetometry, The films exhibit either hysteretic or reversible behaviour depending upon the temperature. This is interpreted as being due to the presence of small, Fee, Go-rich particles of Fee Co in the non-magnetic matrix, giving rise to superparamagnetism at higher temperatures. With the help of low-field susceptibility measurements made on samples cooled in zero field we have been able to determine the distribution of blocking temperatures and thus make an estimate of the size distribution of the particles in the Cu matrix; these have been found to range in diameter from 6 to 12 nm. These results have been compared with values obtained from a measurement of the temperature dependence of the remanence. We have found that, even in such a relatively dilute magnetic system as Cu0.94Co0.06, interactions between magnetic clusters are not negligible. The interaction energy is estimated to be of the order of 1.7 x 10(-3) eV.