1. Graduate Institute of Photonics and Optoelectronics and the Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
2. Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan
3. Department of Photonics and Institute of Electro-optic Engineering, National Yang-Ming Chiao-Tung University, Hsinchu, Taiwan
4. Corning Inc., Corning, NY, USA