1. Department of Physics and Center of Crystal Research, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan
2. Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
3. Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, Texas 77204, USA
4. Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan