Recording simulation beyond 2Tbit/in2 on bit-patterned media with shielded planar head

Simulation Study of High-Density Bit-Patterned Media With Inclined Anisotropy

“…3, where reverse beginning field, , remanence coercivity, , remanence saturation field, , and the switching field width, , are shown. In addition, the reverse beginning fields for easiest initial magnetization [5], Lowest , were also exhibited for media with the anisotropy angle less than 50 , where the initial magnetization pattern was set as in the inset of Fig. 3 so that maximum demagnetizing field is applied to a dot from surrounding dot magnetization.…”

“…The increase in is caused by the opposite magnetostatic field from surrounding dots with opposite magnetization, and the decrease in comes from the demagnetizing field from surrounding dots with the same magnetization. However, the magnetostatic interaction is reversed when the anisotropy of the dots is in the longitudinal direction [2]. The dipole-dipole interaction is changed from negative to positive and the switching field width is decreased.…”

“…Anisotropy angle dependence of down and cross track shift margins for patterned media with inclined anisotropy. and the recording was made on the third track to evaluate adjacent track write at the second track [5]. The nonsaturated initial pattern decreased the cross track shift margin for media with the 30 anisotropy medium.…”

“…The enhanced magnetostatic interaction causes increased switching field width between the lowest and highest reversal fields of the dot array and it reduces the shift margin of writing in the down and cross track directions [1]. We have proposed a method to reduce the effect of the interaction introducing exchange coupling between the magnetic dots [1], and another method which uses in-plane anisotropy [2]. However, the former method requires fabrication of dot arrays with highly controlled exchange coupling between the dots, and the latter requires a high write field when a perpendicular pole head is used.…”