1. Departamento Fisica Materia Condensada, C03, IFIMAC and INC, Universidad Autonoma de Madrid, 28049 Madrid, Spain
2. Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
3. Department of Physics, National Taiwan University, Taipei 10617, Taiwan
4. Department of Physics, Tamkang University, New Taipei City 25137, Taiwan
5. Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
6. Donostia International Physics Center (DIPC), E-20018 Donostia-San Sebastián, Spain
7. IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao, Spain