Magnetic behaviour of some amorphous Er–Co alloys

Magnetic properties in some sputtered RCo2 amorphous alloys (R = rare-earth = Er, Sm, Tb)

“…Nevertheless, magnetisation versus temperature measurements do not reveal a compensation temperature for the thicker sample, probably due to inhomogeneity of the layers [2]. We can note a like-spin glass behaviour below 20 K, which can be given by the Arrot plots shown in Fig.…”

“…This gives strong limitations for our study. The susceptibility χ m = M m /H m versus H m follows a Rayleigh law χ m = χ 0 + αH m , although deviations have been observed by several authors [1,2,12,13]. Magnetostatic effects can justify the observed non-linearities: a square root law of H m was observed for the χ m (H m ) behaviour in the 100 Oe range for the first sample described [1].…”

“…We have investigated a series of amorphous thin films RCo 2 samples having a high T c with a relatively low critical cobalt content (x = 0.68) [1][2][3]. The sperimagnetism of these alloys are confirmed, which are hard magnetically and characterised by a biaxial anisotropy in the film plane.…”

“…By tracing log versus log (H e − NM) around T c and change N to obtain the best line. Due to reduced signal, magnetisation have been carried out on several layers of samples of large depth about 100 m, which allows to confirm an important value of demagnetising field N × M. A strong negative curvature of M 2 can have a good representation in the magnetisation curve versus temperature [2], which shows a mixed transition at low-field with patatoid form (<25 K) ferromagnetic spin glass type and another with a strong peak showing the ferromagnetic transition type up to T c , as far as 300 K. From Babic et al [9] two scenarios obtained are as follows: Fig. 4.…”

“…The magnetic structure of the rare-earth transition-metal amorphous alloys have been intensively studied in earlier works [1][2][3]. Among all researched properties, the magnetization and the shape of hysteresis loops are dependent upon the alloy composition, heat and mechanical treatment.…”