1. Institute of Atomic and Molecular Sciences Academia Sinica Taipei 10617 Taiwan
2. Nano‐Science and Technology Program Taiwan International Graduate Program Academia Sinica Taipei 11529 Taiwan
3. Department of Engineering and System Science National Tsing‐Hua University Hsinchu 30013 Taiwan
4. Department of Chemistry National Taiwan University Taipei 10617 Taiwan
5. Department of Physics National Taiwan University Taipei 10617 Taiwan
6. National Applied Research Laboratories Taiwan Semiconductor Research Institute Hsinchu 30078 Taiwan