A detached pole tip design of perpendicular write heads for high data-rate recording

Calculations of magnetization configurations of SPT head using micromagnetic model

“…Therefore, SPT head has a possibility to follow a high writing frequency up to 0.8 GHz under the calculation conditions examined. But this result also implies that a higher transfer rate over 1 GHz is difficult to attain, which is different from the results given by Bai [1]. They reported that a field rise time of SPT head is 0.17 ns even for a smaller a of 0.05.…”

“…In single-pole-type (SPT) head used for perpendicular magnetic recording it is pointed out that large residual magnetization remains in the main pole even at non-excited state, resulting in collapsing the previously recorded information [1]. Also, several experiments indicate that the information recorded on the neighboring tracks is erased for some reasons.…”

“…In this method, the details of the magnetic domain structures in nanometer size cannot be discussed because B-H curve expresses only averaged magnetic properties in macroregions. On the other hand a micromagnetic model enables us to pursue nano-scale magnetic structures in a recording head [1][2][3][4]. Thus, we applied a micro magnetic model to examine the details of magnetization structures and magnetization process in an SPT head.…”

“…In an SPT head and a double-layered system, it is necessary to take into account the magnetostatic interaction between an SPT head and a medium. Usually this interaction was approximated by ideal mirror effect in micromagnetic calculations [1]. But this method has a possibility to overestimate the head-medium interaction.…”

“…But this method has a possibility to overestimate the head-medium interaction. Also, in the previous works a return pole was neglected [1] or approximated by an analytic method [4]. In our study, a head-medium interaction was directly calculated without any approximation.…”