L1₀-CoPt Bit Patterned Media with Tilted Easy Axis for Ultrahigh Areal Density over 2.5 Tb/in²

Abstract:

Ultrahigh areal density is the key target of hard disk drive technology. Hence, writing field strength from head and switching field, H_sw, of media should be improved. In this work, we propose the one of alternative method to increase data density and reduce H_sw of the media by using tilted easy axis technology for bit patterned media (BPM) at areal density beyond 2.5 Tb/in². Moreover, transition noise and superparamagnetic limit have been eliminated owing to characteristics of BPM. The effect of exchange coupled between adjacent bits, A_dot, of tilted easy axis of BPM is analyzed by micromagnetic simulation software - the object oriented micromagnetic framework based on Landau-Lifshitz-Gilbert equation. The BPM with tilted easy axis perform clearly the reduction of H_sw below perpendicular media and available writing head field. The A_dot of BPM has no effect on decreasing H_sw. Anisotropy and Zeeman energy density of BPM with tilted easy axis are higher and lower than perpendicular BPM, respectively. Thereby, BPM with tilted easy axis have high potentiality to improve H_sw of media at ultrahigh data density.

• Periodical: Advanced Materials Research (Volumes 931-932)
• Pages: 1255-1259
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.931-932.1255
• Online since: May 2014
• Authors: Arkom Kaewrawang*
• Keywords: Bit Patterned Media, L1₀-CoPt, Switching Field, Tilted Easy Axis

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