High-field orientational magnetic phase diagrams of the mixed holmium-yttrium iron garnet Ho{sub 0.43}Y{sub 2.57}Fe{sub 5}O{sub 12}

Abstract

H-T magnetic phase diagrams of the Ho{sub 0.43}Y{sub 2.57}Fe{sub 5}O{sub 12} garnet, due to spin-reorientation transitions, have been determined in the low temperature range (2-30 K) by magnetization measurement under high static magnetic fields (23 T) on [111] and [110] oriented single crystals. It is shown that a very good agreement between computed and observed phase diagrams can be achieved when the free energy is calculated by direct diagonalization of a Hamiltonian including the crystal field (CF) and the exchange interactions considered in the mean-field formalism.