Magnetic properties of thin film GdCoRe amorphous alloys

Thin film amorphous samples of (Gd1-xCox)(1-y)Re-y (a-GdCoRe) have been gro wn using a RF sputtering system. In order to consider these ferrimagnetic a -GdCoRe alloys for application in bubble devices, we have studied the tempe rature dependence of the saturation magnetization (M-s) and coercivity (H-c ) as a function of composition, in the concentration range 0.74 <s <0.84, 0 .08 <y <0.12. From M-s vs. T plots, compensation temperatures (T-comp) have been determined for all samples. The temperature dependence of the coerciv ity (H-c vs. T) displays the sharp maximum at the compensation temperature (T-comp) that is characteristic of ferrimagnetic amorphous alloys. All the samples studied show perpendicular anisotropy. The effect of Re addition on the magnetic properties of a-GdCo alloys will be discussed in comparison t o those of other elements, as Mo. (C) 2001 Elsevier Science B.V. All rights reserved.