Whispering Gallery Modes of Quasi-Periodic Photonic Crystal Lasers Po-Tsung Lee 李柏璁 Department of Photonics & Institute of Electro-Optical Engineering, National Chiao Tung University, Taiwan

Modified Octagonal (8-fold) Quasi-Photonic Crystal (OQPC) Single-Defect Micro-Cavity OQPC Lattice

WGM Lasing & Threshold Dependence on Lattice Periods Threshold – 0.35mW at 1499nm, single-mode lasing Side-Mode Suppression Ratio (SMSR) – 25dB Estimated Quality Factor – 7000 Advantages Very condensed device size (3.5  m X 3.5  m), which is very potential in photonic integrated circuits

WGM Lasing Action and Comparison with Photonic Crystal Laser Lasing Action ： Single-mode lasing at 1574nm with 0.15nm FWHM SMSR ： > 20dB Threshold ： 0.15mW (DQPC D2) < 0.6mW (PC D2) Dodecagonal (12-fold) Quasi-Photonic Crystal (DQPC) D2 Micro-Cavity