1. Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan
2. Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan
3. Department of Electrical Engineering, Yuan Ze University, Taoyuan 32003, Taiwan
4. Department of Polymer Chemistry and Technology, Kaunas University of Technology, Radvilenu Road 19, LT-50254 Kaunas, Lithuania