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 300, Taiwan
3. Department of Physics, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan
4. Department of Applied Science, National Taitung University, Taitung 95092, Taiwan
5. Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan
6. Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan
7. Institute of Analytical and Environment Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan
8. Physics Division, National Center for Theoretical Sciences, Hsinchu 30013, Taiwan
9. Institute of Physics, Academia Sinica, Taipei 11529, Taiwan
10. Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan