{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T20:06:44Z","timestamp":1777493204941,"version":"3.51.4"},"reference-count":28,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2011,7,25]],"date-time":"2011-07-25T00:00:00Z","timestamp":1311552000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Slot waveguides are very promising for optical sensing applications because of their peculiar spatial mode profile. In this paper we have carried out a detailed analysis of mode confinement properties in slot waveguides realized in very low refractive index materials. We show that the sensitivity of a slot waveguide is not directly related to the refractive index contrast of high and low materials forming the waveguide. Thus, a careful design of the structures allows the realization of high sensitivity devices even in very low refractive index materials (e.g., polymers) to be achieved. Advantages of low index dielectrics in terms of cost, functionalization and ease of fabrication are discussed while keeping both CMOS compatibility and integrable design schemes. Finally, applications of low index slot waveguides as substitute of bulky fiber capillary sensors or in ring resonator architectures are addressed. Theoretical results of this work are relevant to well established polymer technologies.<\/jats:p>","DOI":"10.3390\/s110807327","type":"journal-article","created":{"date-parts":[[2011,7,25]],"date-time":"2011-07-25T12:35:29Z","timestamp":1311597329000},"page":"7327-7340","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Modeling of Slot Waveguide Sensors Based on Polymeric Materials"],"prefix":"10.3390","volume":"11","author":[{"given":"Paolo","family":"Bettotti","sequence":"first","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, via Sommarive 14, 38123 Povo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alessandro","family":"Pitanti","sequence":"additional","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, via Sommarive 14, 38123 Povo, Italy"},{"name":"NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, piazza San Silvestro 12, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eveline","family":"Rigo","sequence":"additional","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, via Sommarive 14, 38123 Povo, Italy"},{"name":"Department of Physics, University of Modena and Reggio Emilia, via Campi 213\/A, 41100 Modena, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesco","family":"De Leonardis","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria dell\u2019Ambiente e per lo Sviluppo Sostenibile, Politecnico di Bari, Viale del Turismo 8, 74100 Taranto, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vittorio M. N.","family":"Passaro","sequence":"additional","affiliation":[{"name":"Dipartimento di Elettrotecnica ed Elettronica, Politecnico di Bari, Via E. Orabona 4, 70125 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lorenzo","family":"Pavesi","sequence":"additional","affiliation":[{"name":"Nanoscience Laboratory, Department of Physics, University of Trento, via Sommarive 14, 38123 Povo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2011,7,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"251104","DOI":"10.1063\/1.2408659","article-title":"Polymeric waveguide biosensors with calixarene monolayer for detecting potassium ion concentration","volume":"89","author":"Oh","year":"2005","journal-title":"Appl. Phys. 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