Topological Optimization and Photonic Molecule by Photonic Crystal Microcavity with Enhanced Whispering-Gallery Mode

• Main Author: 林孟穎
• Other Authors: 李柏璁
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/44141714048287454752

碩士 === 國立交通大學 === 光電工程系所 === 97 === This thesis can be divided into two parts. In the first part, based on topology rule, we will investigate microdisk and microgear with whispering-gallery (WG) mode with azimuthal number six and optimize their quality (Q) factors. And we will also investigate microflower topology by further modifying the edge of the grating in microgear. From these simulation results, we analyze and discuss the influence of cavity boundary on Q factors of WG modes. Since there is scale size limitation due to diffraction limitation in microdisk, we also propose a novel design of photonic crystal circular-shaped (CD2) microcavity with well-sustained WG mode. We will apply the same optimization method on this microcavity named photonic crystal microflower CD2 (MFCD2) microcavity. And then this design is realized by a series fabrication processes and the measurement results will be analyzed and discussed. In part two, we will introduce the photonic molecules composed by microdisk and photonic crystal microcavity. We also propose a brand new photonic molecule (PM) design composed by two identical photonic crystal CD2 microcavity membranes in vertical direction named double-layer PM (DLPM). We will investigate and discuss the basic tunable PM states modal properties by 3D FDTD simulations, including Q factor and wavelength. And then we will develop the related fabrication process based on designed GaAs epitaxial structure. This will include the process by changing patterns design, periods of the pattern, the windows and holes size, and dry / wet etching time.