Bueno Guillén, Francisco JavierEsteban Martínez, ÓscarDíaz Herrera, NataliaNavarrete Fernández, María CruzGonzález Cano, Agustín2023-06-202023-06-202004-03-101559-128X10.1364/AO.43.001615https://hdl.handle.net/20.500.14352/50967© 2004 Optical Society of America. We thank E. Bernabeu for his valuables comments and suggestions and C. Cosculluela from the Departamento de Física Aplicada of the Universidad de Zaragoza, Spain, for helping us with the devices’ elaboration. This research has been partially supported by European Union project Multiparametric In Situ Spectroscopic Measuring System for Coastal Monitoring, contract EVK3-CT2000-00519, and Spanish project Aplicación de sensores de fibra óptica al control in-situ de parámetros físicos el medio acuático, Programa Nacional de Recursos Naturales, Ministerio de Ciencia y Tecnología, ref. REN 2001-1495.A novel, to our knowledge, device based on a tapered optical fiber with a double-layer deposition including a metallic media is presented, and its properties are studied. The main novelty of the device consists of the introduction of a dielectric layer, whereas the systems depicted in the literature are simply metal-coated tapered fibers. The presence of the dielectric layer permits one to tune the response of the device to the refractive index of the surrounding medium. We have proved the suitability of this scheme for refractive-index sensing by depicting two measurement modes, namely, total power attenuation and spectral transmittance.engjournal articlehttp://dx.doi.org/10.1364/AO.43.001615http://www.opticsinfobase.orgopen access535Surface-Plasma ModesResonant ExcitationFiberoptic SensorsSingle-ModeFiltersÓptica (Física)2209.19 Óptica Física