1. Department of Materials Science and Engineering, National Tsing-Hua University, Hsinchu, 30013, Taiwan
2. Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan
3. Department of Physics, National Sun Yat-Sen University, Kaohsiung, 80424, Taiwan
4. Instrument Center, National Tsing Hua University, Hsinchu, 30013, Taiwan