Acoustic longitudinal mode coupling in w-shaped Al/Ge Co-doped fibre

作     者：李宏亮 张巍 黄翊东 彭江得 

作者机构：State Key Laboratory on Integrated Opto-electronics Electronic Engineering Department Tsinghua University 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2011年第20卷第10期

页      面：281-289页

核心收录：

学科分类：12[管理学] 1201[管理学-管理科学与工程(可授管理学、工学学位)] 070207[理学-光学] 07[理学] 08[工学] 081201[工学-计算机系统结构] 0702[理学-物理学] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：supported in part by the National Natural Science Foundation of China (Grant No. 60777032) 973 Program of China(Grant No. 2010CB327600) the Science Foundation of Beijing (Grant No. 4102028) 

主　　题：Brillouin scattering acoustic mode coupling fibre sensing optical fibre design 

摘      要：This paper proposes a novel fibre structure aiming at distributed temperature and strain sensing. Utilizing Al2O3 and CeO2 as dopants to form a w-shaped acoustic waveguide, it realizes modal coupling between longitudinal acoustic modes of its inner and outer core layers, leading to a dual-peak or multi-peak Brillouin gain spectrum. The relationship between the acoustic mode coupling properties and the fibre materials, doping concentrations and structural parameters are investigated, showing that the positions of mode coupling points in acoustic dispersion curves and the coupling intensities can be designed flexibly. A specific fibre design for the discriminative sensing of temperature and strain under a pump wavelength of 1.55 μm is given. The responses of its Brillouin gain properties on temperature and strain are analysed theoretically, demonstrating its potential for distributed fibre Brillouin sensing.