1. Department of Physics Shaanxi University of Science and Technology Xi'an Shaanxi 710021 China
2. School of Physics Georgia Institute of Technology 837 State Street NW Atlanta GA 30332 USA
3. Key Lab of In‐Fiber Integrated Optics of Ministry of Education of China and Key Lab of Photonic Materials and Devices Physics for Oceanic Applications of Ministry of Industry and Information Technology of China Harbin Engineering University Harbin Heilongjiang 150001 China
4. School of Physics and Astronomy Cardiff University Queen's Buildings North Building 5 The Parade, Newport Road Cardiff CF24 3AA UK
5. School of Physics and Optoelectronic Engineering Foshan University Foshan Guangdong 528000 China
6. Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China
7. College of Optoelectronic Engineering Guilin University of Electronic Technology Guilin Guangxi 541004 China
8. Faculty of Computing Engineering and Science University of South Wales Pontypridd CF37 1DL UK
9. Faculty of Business and Physical Sciences Aberystwyth University Aberystwyth Ceredigion Wales SY23 3FL UK
10. College of Physics and Information Technology Shaanxi Normal University Xi'an Shaanxi 710119 China