1. Graduate Institute in Electro-Optical Engineering, Tatung University, Taipei104, Taiwan, Center for Condensed Matter Sciences, National Taiwan University, Taipei 106, Taiwan, Materials Science and Engineering, National Taiwan University, Taipei106, Taiwan, Graduate Institute of Materials Science and Technology, National Taiwan University of Science and Technology, Taipei 106, Taiwan, Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan, and Institute of...