Magnetic properties of ferrimagnetic rare-earth—transition-metal films and multilayers

Abstract

In this paper we present a brief report on magnetization studies of three different types of rare-earth—transition-metal ferrimagnetic thin films. The first consists of compositionally modulated Gd 0.15Fe 0.85/Gd 0.40Fe 0.60 where the two compositions are on different sides of the magnetic compensation point (Gd 0.26Fe 0.74) at room temperature. The compositionally modulated layers therefore form an artificial (macroscopic) superlattice antiferromagnet which exhibits both spin-flop transitions and enhanced in-plane anisotropy owing to classical dipolar effects. We also report magnetization measurements on a homogeneous film of Tb 0.23Fe 0.77, which exhibits large perpendicular anisotropy typical of amorphous TbFe thin films as well as a spin-flop transition near 60 kOe. Finally, we present data on a film of Gd 0.40Fe 0.60(300 Å)/Fe(10 Å)/Pd(100 Å)/Fe(30 Å) which demonstrates a practical method of determining the strength of ferromagnetic coupling between two magnetic layers from simple magnetization measurements.