Multi-parameter optical gauge based on mode coupling effect in asymmetric index multi-core fibres

• DOI: 10.1016/j.optlaseng.2022.107047
• Publication Date: 2022-03-22T17:11:26Z
• Authors: Oskar Arrizabalaga; Qi Sun; Timothy Lee; Joseba Zubia; Javier Velasco Pa...; Idurre SÁez De Oc...; Axel SchÜlzgen; Rodrigo Amezcua-C...; Gilberto Brambilla; Martynas Beresna
• Keywords: multicore fibre-based sensors; multiparameter sensor; 0103 physical sciences; 0202 electrical engineering, electronic engineering, information engineering; optical fibre-based sensors; mode coupling effect; 02 engineering and technology; optical gauges; 530; 01 natural sciences; 620

An optical gauge based on coupled multi-core fiber is proposed and experimentally demonstrated. By using direct laser writing to selectively break the fiber index profile symmetry, asymmetric mode coupling between cores is introduced. This allows to fabricate optical gauges with the ability to detect and differentiate different types of deformation in structures using just a single sensor. The fabricated optical gauges are compared with calibrated commercial gauges and fiber Bragg gratings as strain, vibration and curvature gauge. The tests indicate superior performance of this novel optical gauge over the commercially available sensors and offer the highest sensitivities. The proposed technology could be key to the fabrication of new fiber-based sensing devices with more capabilities and better features than previously achieved.<br/>This work has been funded in part by the Fondo Europeo de Desarrollo Regional (FEDER) , in part by the Ministerio de Ciencia, Innovacion y Universidades under projects RTI2018-094669-B-C31 in part by the GobiernoVasco/Eusko Jaurlaritza ELKARTEK KK-2021/00092 and ELKARTEK KK-2021/00082. The authors also acknowledge UKRI for partial support through research grants EP/S013776/1; NE/S012877/1; NE/T005890/1<br/>