1. Department of Physics National Taiwan University 1, Sec. 4, Roosevelt Rd. Taipei 10617 Taiwan
2. Institute of Physics Academia Sinica 128, Sec. 2, Academia Rd. Taipei 11529 Taiwan
3. Graduate School of Engineering Osaka University 2‐1 Yamadaoka Suita Osaka 565‐0871 Japan
4. Photonics Center Graduate School of Engineering Osaka University 2‐1 Yamadaoka Suita Osaka 565‐0871 Japan
5. Molecular Imaging Center National Taiwan University 1, Sec 4, Roosevelt Rd. Taipei 10617 Taiwan
6. Brain Research Center National Tsing Hua University 101, Sec. 2, Kuang‐Fu Rd. Hsinchu 300044 Taiwan