Optimized active multicore fiber bending sensor

Abstract

Keywords:Multicore waveguide Er 3+ -doping Modal interferometer Bending sensor A B S T R A C TWe present a study of the feasibility of transforming the multicore fiber in a supermode-interference based bending sensor into an active stage. By compensating the antisymmetric supermode losses for high curvatures, fringe visibility is improved and the sensor operating range can be extended. For a given multicore fibre length and Er 3+ -ion concentration sensor calibration curves allow assessing the bending radius by measuring the visibility as a function of the input pump power. The Er 3+ -ion concentration, available input pump power and multicore fiber length set the minimum bending radius that could be measured. (J.A. Vallés).Optical Materials xxx (xxxx) xxx-xxx 0925-3467/

Advances in Multicore Fiber Interferometric Sensors

“…Thanks to the large spatial distribution of the fiber mode field of supermodes, bending will easily distort the mode field, which can change the mode loss of each supermode and the phase difference between the supermodes. As a result, bending will result in wavelength shifts [ 93 ], light power variation [ 15 ], and fringe visibility changes [ 107 ] in the SMI, which has been widely used for the high-sensitivity measurement of bending/strain-related external perturbations, such as bending [ 15 , 93 , 94 , 95 , 96 , 107 , 108 , 109 , 110 , 111 , 112 ], vibration [ 16 , 18 , 20 , 113 , 114 , 115 , 116 , 117 ], and strain [ 118 , 119 ]. Furthermore, by using an MCF with asymmetrically distributed cores, the SMI can be used to sense the bending direction.…”