1. Key Laboratory of In-fiber Integrated Optics of Ministry of Education, College of Science, Harbin Engineering University, Harbin, China
2. Photonics Research Center, Technological University Dublin, Dublin, Ireland
3. Optical Fibre Sensors Research Centre, Department of Electronic and Computer Engineering, University of Limerick, Limerick, Ireland
4. Photonics Research Center, Guilin University of Electronic Technology, Guilin, China