APPLICATION OF MAGNETIC REORIENTATION PHASE TRANSITION IN THE STUDY OF EXCHANGE ANISOTROPY

A Magnetic Reorientation Phase Transition (MRPT) was discovered in 1981 in Molecular-Beam-Epitaxially (MBE) grown thin iron (Fe) films on (110) GaAs substrates. The reorientation transition was characterized by the sudden switching of the in-plane magnetization in the Fe films. Subsequent to this work it was discovered that at low temperatures, the natural oxide on these films becomes antiferromagnetic and provides an exchange anisotropy field. In a ferromagnetic material such as Fe, because of the anisotropic magnetoresistance effect the resistance depends on the angle between the current and the magnetization which is in turn determined by the magnetic energy expression. This paper reviews the application of the MRPT in the study of exchange anisotropy in both the experimental and theoretical aspects.