Affiliation(s): School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, China; State Key Laboratory of Luminescent Materials and Device, South China University of Technology, Guangzhou 510641, China; Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, South China University of Technology, Guangzhou 510641, China; Guangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and Devices, South China University of Technology, Guangzhou 510641, China; less