Affiliation: | 1. Department of Physics, Yunnan University, Kunming, Yunnan, China;2. Yunnan Key Laboratory for Micro/Nano Materials and Technology, Yunnan University, Kunming, Yunnan, China;3. Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada;4. Department of Materials Science and Engineering, University of Toronto, Toronto, Ontario, Canada |