Effect of Compression upon the Magnetic Behaviour of Magnetite in Thermal Cycles across the Magnetocrystalline Isotropic Point

Abstract

THE value of the first magnetocrystalline isotropic constant, K₁, of magnetite changes at low temperature¹. This results in an isotropic point at a temperature T_K of about −143° C^2,3, where there is effectively zero magnetocrystalline anisotropy. A transition of remanence and associated memory are observed in thermal cycles across $T_{K^{\text{4,5}}}$. We have observed that the memory and the low-temperature moment are increased when the thermal cycles are carried out under elastic compression.