Effect of intergranular exchange on thermal energy barrier distribution in longitudinal magnetic recording

Micromagnetic simulations have been performed to examine thermal energy barrier distributions in longitudinal recording. Results show that intergranular exchange reduces the energy barrier distribution width compared to the width of the physical volume distribution, which agrees well with experimental measurements. The rms average energy barrier is almost unchanged by the interactions. Intergranular magnetostatic interactions also decrease the thermal energy barrier width but only for either small exchange or small volume distributions. These results indicate that a measurement of energy barrier width reduction can be used to estimate the intergranular exchange of a typical longitudinal medium.