Plasmonic near field transducer of nanocomposite with distributed feedback

Abstract

In this paper, we present a novel near field transducer (NFT) design concept for heat assisted recording. In this design, metal bars separated by thin dielectric are used to form a resonance plasmonic grating with distributed feedback (DFB). The motivation for such structure design is the use of dielectric separation for enhancing the material stability at elevated temperature so that best materials can be used without compromising much needed plasmonic properties. COMSOL Multiphysics software is used to simulate the plasmonic excitation and propagate to provide a detailed performance analysis on novel NFT with a nanocomposite structure to create distributed optical feedback (DFB) for maintaining the plasmonic resonance. The NFT is composed of an array of Au rectangular gratings separated by a constant gap, with each grating component embedded in the dielectric medium. It is shown that the grating based NFT could have the same NFT efficiency compared with a solid piece of Au NFT of the same geometric dimensions.