Optical field enhancement for heat-assisted magnetic recording system using Photonic Crystal waveguide

The Photonic Crystal (PC) waveguide designed for the optical delivery system for HAMR is proposed. Two-dimensional (2D) models of the single-piece PC waveguides are initially designed using square and triangular lattice structures made of silicon surrounded by an array of air holes, with two input wavelengths of interest: 633 and 1,550 nm. The wave guiding component is formed by removing a center row of air holes with a 90° sharp turn created at the input, assuming a normal incident field to the waveguide. It is found that the designed triangular lattice structures can easily associate both transverse electric (TE) and transverse magnetic (TM) modes while only TE mode is possible for the square lattice. The numerical simulation shows that the overall transmission efficiency of both structures is greater than 75%, and almost 80% can be achieved especially with the TE rectangular lattice structure.