The Effects of Magnetic Properties of L1₀-FePt/Fe Based Exchange Coupled Composite Media on Switching Field

Abstract:

The L1₀-FePt/Fe based exchange coupled composite (ECC) bilayer media is one candidate to extend the areal density of magnetic recording system and solve writability issue in trilemma. L1₀-FePt is the great high magnetic anisotropy material. Therefore, the magnetic parameters of this material such as magnetocrystalline anisotropy constant, K_u, saturation magnetization, M_s, and exchange coupling between a soft/hard interface, are important on magnetic material properties. In this work, the effects of magnetic parameters on magnetic properties of L1₀-FePt/Fe based ECC bilayer media are simulated by the object oriented micromagnetic framework based on Landau-Lifshitz-Gilbert equation. The ECC bilayer media can reduce switching field, H_sw, of media lower than available writing head field. Hence, writability issues of high K_u media can be achieved. Reducing H_sw of ECC bilayer media obtains from lower K_u and higher M_s values. This work can achieve writing capability of a future magnetic recording system.

• Periodical: Advanced Materials Research (Volumes 931-932)
• Pages: 271-275
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.931-932.271
• Online since: May 2014
• Authors: Warunee Tipcharoen, Arkom Kaewrawang*, Apirat Siritaratiwat, Kittipong Tonmitra
• Keywords: Exchange Coupled Composite Media, Fe, L1₀-FePt, Magnetocrystalline Anisotropy Constant, Saturation Magnetization, Switching Field

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