Intrinsic coercive force of rare earth iron garnets near the compensation temperature

Abstract

The intrinsic coercive force of single crystals of those rare earth iron garnets having magnetization compensation temperatures greater than 77°K has been measured as a function of temperature and orientation with particular emphasis given to the temperature range near the magnetization compensation temperature. A single peak in the intrinsic coercive force was observed at the magnetization compensation temperature for almost all of the samples and for all principal orientations. Typically, the peak value of the coercive force was 50 Oe independent of material and orientation with a temperature difference between half-maximum points of less than 3°K. A single-domain model is proposed which concludes that the iron sublattice is primarily responsible for the coercive force near the magnetization compensation temperature and that complete magnetization compensation cannot occur due to the susceptibility of the rare earth sublattice. This leads to a finite coercive force at the magnetization compensation temperature.