1. Semiconductor Industry and Technology Research Institute Jimei University Xiamen 361021 China
2. Department of Electrical and Computer Engineering Ajou University Suwon 16499 South Korea
3. Department of Electrical and Computer Engineering University of Virginia Charlottesville VA 22904 USA
4. Department of Photonics National Cheng Kung University Tainan 701 Taiwan Republic of China
5. Department of Electrical Engineering Yuan Ze University Taoyuan 320 Taiwan Republic of China