[OPTICAL REVIEW Vol. 21, No. 5 (2014) 568-575]
© 2014 The Japan Society of Applied Physics
Simulation on Near-Field Light Generated by Metal Nano-Dot on GaAs Substrate for Heat Source of Heat-Assisted Magnetic Recording
Ryuichi KATAYAMA*
Department of Information Electronics, Faculty of Engineering, Fukuoka Institute of Technology, Fukuoka 811-0295, Japan
(Received November 30, 2013; Accepted May 15, 2014)
Heat-assisted magnetic recording (HAMR) is promising for achieving more than 1 Tb/inch2 recording density. A near-field transducer (NFT), which forms a hot spot of 10–100 nm in diameter on a recording medium, is necessary in HAMR. In this study, localized surface plasmons generated by a metal nano-dot in a novel device for a heat source of heat-assisted magnetic recording were analyzed using a simple model in which a metal hemisphere was formed on a GaAs substrate and a quasi-electrostatic approximation. The scattering and absorption efficiencies as well as the enhancement factor were investigated for several kinds of metal. As a result, their dependence on the wavelength and the polarization direction of the incident light was clarified.
Key words: heat-assisted magnetic recording, near-field transducer, near-field light, localized surface plasmon, metal nano-dot, quasi-electrostatic approximation
*E-mail address: r-katayama@fit.ac.jp