Microwave Assisted Magnetization Reversal on Exchange Coupled Composite Media

Abstract:

To overcome superparamagnetic limit, microwave assisted magnetic recording (MAMR) is one interesting magnetic recording technology. Therefore, the effect of microwave on magnetization reversal in media should be analyzed. In this work, we propose the MAMR to decrease switching field (coercivity, Hsw) in exchange coupled composite (ECC) media by using the micromagnetic simulation based on the Landau - Lifshitz - Gilbert equation. The Hsw of single layer and ECC media without microwave field is 110.90 and 7.7 kOe, respectively. When the oscillating microwave field is added, Hsw of single layer media with microwave frequency of 2.5 - 40 GHz is lower than 110.90 kOe. Likewise, Hsw of ECC media with microwave frequency of 5 - 16 GHz is lower than 7.7 kOe and has the lowest value of 4.9 kOe at frequency of 10 GHz. The results from this work lead to solve superparamagnetic limit and increase areal density in hard disk drive.

• Periodical: Advanced Materials Research (Volumes 931-932)
• Pages: 1265-1269
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.931-932.1265
• Online since: May 2014
• Authors: Naruemon Wannawong, Warunee Tipcharoen, Arkom Kaewrawang*
• Keywords: ECC Media, Hard Disk Drive, Microwave Assisted Magnetic Recording

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