Time Dependent Magnetization Reversal in TbFeCo Perpendicular Magnetic Recording Media.

Abstract

In this work we report on experimental analysis and numerical simulations of the time decay of magnetization in the films of amorphous TbFeCo alloys. It is shown that experimental results can be explained on the basis of an incoherent thermally activated subnetwork magnetization reversal model. Thermally activated reversal of transition metal subnetwork and associated compensating reversal of the antiferromagnetically coupled rare-earth subnetwork may result in effective stabilization of the net film magnetization. The unique combination of a small activation diameter Da = 5-6nm and high thermal stability parameter k∼250 makes TbFeCo amorphous films an excellent candidate for perpendicular recording medium at over 100 Gbit/in2 areal recording density.