Simulated temperature dependence of exchange bias field in exchange coupled FeRh/FePt bilayer: relevance in magnetic recording media

We describe in the present study the results of simulations of the effect of temperature on the exchange bias field of a ferromagnetic FePt and antiferromagnetic FeRh bilayer structure, which is of practical significance in heat assisted magnetic recording media. The exchange bias field of the examined bilayer system did not exhibit a monotonic dependence on temperature, instead a crossover from negative to positive exchange bias at 110 K and another crossover from positive to negative exchange bias at 330 K were observed. This intriguing behaviour is explained on the basis of interface exchange coupling between ferromagnetic FePt and the spin glass-like FeRh.