Del Villar, IgnacioSocorro Leránoz, Abián BentorCorres Sanz, Jesús MaríaArregui San Martín, Francisco JavierMatías Maestro, Ignacio2018-03-282018-03-2820141559-128X (Print)2155-3165 (Electronic)10.1364/AO.53.003913https://academica-e.unavarra.es/handle/2454/28109Thin-film coated single-mode–multimode–single-mode (SMS) structures have been analyzed both theoretically and experimentally with the aim of detecting different refractive indices. By adequate selection of the thickness of the thin film and of the diameter of the multimode segment in the SMS structure, a seven-fold improvement can be obtained in the sensitivity of the device to the surrounding medium refractive index, achieving a maximum sensitivity of 1199.18 nm∕refractive index unit for the range of refractive indices from 1.321 to 1.382. Using layer-by-layer self-assembly for deposition, both on the cladding and on the tip of the multimode segment, allows the reflected power to increase, which avoids the application of a mirror on the tip of the multimode segment.application/pdfeng© 2014 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited.Fiber optics sensorsThin filmsInterferometryArtículo / ArtikuluaAcceso abierto / Sarbide irekiainfo:eu-repo/semantics/openAccess