1. Leibniz Institute of Photonic Technology, Albert-Einstein Straße 9, 07745 Jena, Germany
2. Department of Materials Science and Tsukuba Research Center for Energy Materials Science (TREMS), Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan
3. Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
4. Research Center for Applied Sciences, Academia Sinica, 128 Sec. 2, Academia Road, Nankang District, 11529 Taipei, Taiwan
5. Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University Jena, 07743 Jena, Germany
6. Department of Electrophysics, National Yang Ming Chiao Tung University, 1001 University Road, 30010 Hsinchu, Taiwan