1. Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 116, Taiwan
2. Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
3. Taiwan Semiconductor Research Institute, National Applied Research Laboratories, 300091 Hsinchu, Taiwan
4. Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan
5. Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan
6. Graduate Institute of Energy Engineering, National Central University, Taoyuan 320317, Taiwan