1. Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei City 106319, Taiwan
2. Department of Materials Science and Engineering, National Taiwan University, Taipei City 106319, Taiwan
3. Department of Physics, University of Stuttgart, Stuttgart 70174, Germany
4. Department of Chemistry, National Tsing Hua University, Hsinchu 300044, Taiwan
5. International Ph.D. Program in Biomedical Engineering, Taipei Medical University, New Taipei City 235603, Taiwan
6. Graduate Institute of Nanomedicine and Medical Engineering, Taipei Medical University, New Taipei City 235603, Taiwan