Affiliation: | 1. Department of Physics, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan, Republic of China;2. Graduate Institute of Electronics Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan, Republic of China;3. Institute of Optoelectronic Sciences, National Taiwan Ocean University, No.2, Pei‐Ning Road, Keelung 224, Taiwan, Republic of China;4. Center for Emerging Material and Advanced Devices, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan, Republic of China |