High sensitivity torsion sensor based on Er3+ doped multicore fiber ring laser

This work reports a torsion sensor based on a fiber-ring laser (FRL), whose active element is a 58 cm segment of three inline core erbium-doped fiber (EDF-3C). In this architecture, the multicore fiber simultaneously provides optical gain and torsion transduction. The applied twist alters the inter-...

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Detalles Bibliográficos
Autores: Correa Serrano, Ángel Ignacio, Galarza Galarza, Marko, Leventoux, Yann, Jamier, Raphael, Roy, Philippe, Pérez Herrera, Rosa Ana, López-Amo Sáinz, Manuel
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2025
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/55865
Acceso en línea:https://hdl.handle.net/2454/55865
Access Level:acceso abierto
Palabra clave:Erbium-doped fiber ring laser
Multicore fiber
Torsion sensing
Descripción
Sumario:This work reports a torsion sensor based on a fiber-ring laser (FRL), whose active element is a 58 cm segment of three inline core erbium-doped fiber (EDF-3C). In this architecture, the multicore fiber simultaneously provides optical gain and torsion transduction. The applied twist alters the inter-core coupling, producing a gain splitting that appears as two laser peaks. The wavelength separation between the peaks encodes the torsion magnitude, whereas their relative powers reveal the twist direction. By fine-tuning the polarization controller, bidirectional operation remained stable over a ±70° range without mode extinction. The differential wavelength shift exhibited linear sensitivities of 0.013 nm/° for negative torsion and 0.019 nm/° for positive torsion. Direction discrimination is further enhanced by analyzing the peak-power difference and is additionally optimized with a function-fitting neural network trained on the measured spectra. The machine learning model achieved R² = 0.9999 and an angular detection limit of 1.28 × 10-4°.