Numerical simulations of write head and spin-toque oscillator for microwave-assisted magnetic recording

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K06321
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Electron device/Electronic equipment
• Research Institution: Niigata Institute of Technology
• Principal Investigator: KANAI YASUSHI 新潟工科大学, 工学部, 教授 (00251786)
• Co-Investigator(Renkei-kenkyūsha): GREAVES Simon
• Research Collaborator: MURAOKA Hiroaki
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 高周波アシスト磁気記録 / スピントルク発振素子 / 記録ヘッド / マイクロマグネティック解析シミュレーション

Outline of Final Research Achievements

Spin-torque oscillator (STO) and write head used for microwave-assisted magnetic recording (MAMR), one candidate for the future perpendicular magnetic recording, was investigated by using a computer simulation called micromagnetic simulation. We found that (1) once STO was inserted into write head main pole and trailing shield gap, it was hard to obtain a stable oscillation. Therefore, obtaining a stable STO oscillation is the key to realize the MAMR technology. To obtain a stable STO oscillation (2) small area STO had comparably large high-frequency field for its small area and oscillated stably, (3) STO tilted with regard to the medium surface oscillation stably, (4) non-parallel write head gap lead to a stable STO oscillation.

Free Research Field

工学

Academic Significance and Societal Importance of the Research Achievements

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