Influence of Thermal Gradient and Cooling Rate on Writability in Heat-Assisted Magnetic Recording
Year: 2025
Type: article
Abstract: We analyze the influence of thermal gradient and cooling rate on writability in 4 Tbpsi shingled heat-assisted magnetic recording employing a stochastic calculation. We separate the bit error rate bER for each grain column in 2 bits of data and focus on the mean magnetization reversal number per unit time ๐- for the medium in the recording direction during writing. We introduce the medium writing temperature ๐ฅ๐med and time ๐med, which are temperature and time ranges, respectively, where the ๐- value is larger than 1 ns-1. We also introduce the Curie temperature variation time ๐Tc and the field end temperature ๐end. The ๐med and ๐Tc values are functions of the cooling rate, which is the product of the thermal gradient and the linear velocity. In contrast, the ๐end value is a function of the thermal gradient only. When the writing field is small, write-error and erasure-before-write are mainly dominant, and the bER value is determined by the ๐med and ๐Tc values, respectively. When the writing field is large, erasure-after-write is mainly dominant, and the bER value is determined by the ๐end value in addition to the ๐Tc value.
Authors: T. Kobayashi, Y. Nakatani, I. Tagawa
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4417010638