1. Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 30010, Taiwan
2. Université de Haute-Alsace, CNRS, IS2M UMR 7361, F-68100 Mulhouse, France
3. Université de Strasbourg, 67081 Strasbourg, France
4. Department of Physics, Tamkang University, No. 151, Yingzhuan Road, Tamsui
District, New Taipei City 25137, Taiwan
5. Department of Chemistry, National Taiwan Normal University, 162, Section 1, Heping E. Road, Taipei 106, Taiwan
6. Institute of Physics, National Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 30010 Taiwan