Theoretical analysis of the mode coupling induced by heat of large-pitch micro-structured fibers  

作　　者：张海涛 陈丹 郝杰 闫平 巩马理 

机构地区：[1]Center for Photonics and Electronics,State Key Laboratory of Tribology,Department of Precision Instruments,Tsinghua University [2]Southwest Institute of Technical Physics

出　　处：《Chinese Physics B》2015年第2期176-180,共5页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.61475081)

摘　　要：In this paper,a theoretical model to analyze the mode coupling induced by heat,when the fiber amplifier works at high power configuration,is proposed.The model mainly takes into consideration the mode field change due to the thermally induced refractive index change and the coupling between modes.A method to predict the largest average output power of fiber is also proposed according to the mode coupling theory.The largest average output power of a large pitch fiber with a core diameter of 190 μm and an available pulse energy of 100 mJ is predicted to be 540 W,which is the highest in large mode field fibers.In this paper,a theoretical model to analyze the mode coupling induced by heat,when the fiber amplifier works at high power configuration,is proposed.The model mainly takes into consideration the mode field change due to the thermally induced refractive index change and the coupling between modes.A method to predict the largest average output power of fiber is also proposed according to the mode coupling theory.The largest average output power of a large pitch fiber with a core diameter of 190 μm and an available pulse energy of 100 mJ is predicted to be 540 W,which is the highest in large mode field fibers.

关 键 词：fiber amplifier large pitch fiber mode coupling 

分 类 号：TN722[电子电信—电路与系统]