1. Department of Physics, National Sun Yat-sen University, Kaohsiung80424, Taiwan
2. Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371, Singapore
3. Physics Division, National Center for Theoretical Sciences, Taipei10617, Taiwan
4. Center for Theoretical and Computational Physics, National Sun Yat-sen University, Kaohsiung80424, Taiwan
5. Department of Physics, National Tsing Hua University, Hsinchu30013, Taiwan