1. Key Laboratory of In-fiber Integrated Optics; Ministry Education of China; Harbin Engineering University; Harbin 150001 China
2. Photonics and Optical Communications; School of Electrical Engineering and Telecommunications; University of New South Wales; Sydney 2052 NSW Australia
3. Bruker Nano GmbH; Am Studio 2D; Berlin 12489 Germany
4. Key Laboratory of Materials for High Power Laser; Shanghai Institute of Optics and Fine Mechanics; CAS; Shanghai 201800 China
5. Optical Fibre Sensors Research Centre; Department of Electronic and Computer Engineering; University of Limerick; Limerick V94 T9PX Ireland