Pacheco-Peña, VíctorBeruete Díaz, MiguelRodríguez Ulibarri, PabloEngheta, Nader2019-05-012019-05-0120191367-2630 (Print)1367-2630 (Electronic)10.1088/1367-2630/ab116fhttps://academica-e.unavarra.es/handle/2454/32994In this paper we perform an in-depth theoretical studyofa sensing platform based on epsilon-near- zero (ENZ) metamaterials. The structure proposed for sensing is a narrow metallic waveguide channel. An equivalent circuit model is rigorouslydeduced using transmission line theory, considering several configurations for a dielectric body (analyte sample) inserted within the narrow channel, showing good agreement with results obtained from numerical simulations. The transmission line model is able to reproduce even the most peculiar details ofthe sensing platform response. Its performance is then evaluated byvarying systematically the size, position and permittivity ofthe analyte, and height ofthe ENZ channel. It is shown that the sensor is capable ofdetecting changes in the permittivity/ refractive index or position even with deeplysubwavelength analyte sizes (∼0.05λ0), giving a sensitivity up to 0.03m/RIU and a figure ofMerit∼25. The effective medium approach is evaluated by treating the inhomogeneous cross-section ofthe analyte as a transmission line filled with a homogeneous material.13 p.application/pdfeng© 2019 The Author(s).Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence.Epsilon-near-zeroMetamaterialsSensingMetamaterial sensorSubwavelength sensingArtículo / ArtikuluaAcceso abierto / Sarbide irekiainfo:eu-repo/semantics/openAccess