title: Specklegram in a grapefruit fiber and its response to external mechanical disturbance in a single-multiple-single mode fiber structure.
abstract: Specklegram in multimode fiber has successfully been used as a sensor for detecting mechanical disturbance. Speckles in a multimode pure silica grapefruit fiber are observed and compared to that of a step-index multimode fiber, showing different features between them. The sensitivities to external disturbance of two kinds of fiber were measured, based on single-multiple-single mode (SMS) fiber structure. Experimental results show that the grapefruit fiber shows higher sensitivity than does the step-index multimode fiber. The transmission spectrum of the grapefruit fiber was measured as well, showing some oscillation features that are significantly different from that of a step-index multimode fiber. The experiments may provide suggestions to understand the mechanisms of light propagation in grapefruit fibers.
authors.affiliation: Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800211, 201800, Shanghai, China.
authors.forename: Yuntao
authors.initials: Y
authors.lastname: Wang
authors.forename: Haiwen
authors.initials: H
authors.lastname: Cai
authors.forename: Ronghui
authors.initials: R
authors.lastname: Qu
authors.forename: Zujie
authors.initials: Z
authors.lastname: Fang
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Marin
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Meunier