Simulation on near-field light generated by a semiconductor ring resonator with a metal nano-antenna for heat-assisted magnetic recording

Abstract

Heat-assisted magnetic recording (HAMR) is a promising technology for achieving more than 1 Tbit/inch2 recording density. A near-field transducer (NFT), which forms a small light spot on a recording medium, is necessary in HAMR. However, the heat generated by the NFT would melt the NFT itself. To solve this problem, the authors have proposed a novel device, in which a metal nano-antenna is attached to a semiconductor ring resonator. In this paper, the relationship between the various design parameters of the device and the near-field light was investigated through a numerical simulation to optimize the structure of the device. The simulation was conducted using the finite element method based on a two-dimensional model. It was found that the electric field at the tip of the nano-antenna depends on the type of eigenmode, the length of the nano-antenna, and the distance between the ring resonator and the nano-antenna.