Micromagnetic simulations for terabit/in2 head/media systems

Bit-patterned (BP) recording is a candidate for extending magnetic data storage towards 10 Tb/in2 bit densities. An analysis of the design tolerances is carried out using dynamic micromagnetic simulations and statistical models. The effects of distributions of the magnetic material properties on phase margin and addressability error-rate during writing are investigated. At 1.3 Tb/in2 a rapid increase of the error-rate is observed when the write-synchronization deviates from the optimum phase φ0. Estimates of the fabrication and write-synchronization tolerances are derived from the phase margins. It is shown that the switching-field distribution (from intra-island variations and inter-island interactions) as well as the fabrication and synchronization tolerances must be tightly controlled for Tb/in2 applications. At ultra-high densities, BP media may need to be combined with energy-assisted writing, which is referred to as second-generation BP recording.