1. Department of Photonics, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
2. Semiconductor Research Center, Hon Hai Research Institute, Taipei, Taiwan
3. College of Photonics, Institute of Lighting and Energy Photonics, National Yang Ming Chiao Tung University, Tainan, Taiwan
4. Graduate Institute of Photonics and Optoelectronics and the Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan