{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T15:17:21Z","timestamp":1777475841047,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,7,10]],"date-time":"2020-07-10T00:00:00Z","timestamp":1594339200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Photonics"],"abstract":"<jats:p>A study on the design, simulation and characterization of a reconfigurable terahertz (THz) filter, composed of two frequency-selective surfaces (FSSs) with applications on sensor devices in general and highly sensitive stress sensors, is presented in this paper. Using the developed theoretical model, we found out that by careful tuning the wire parameters, it is possible to control the filter sensitivity and also the energy transmission and reflection that passes through the structure. Numerical modelling of both the mechanical and electromagnetic components (using the elasticity equation and Maxwell\u2019s equations, respectively) has been undertaken for two types of the device assemblies based on different thermoplastic polymers transparent to the THz radiation, namely: high-density polyethylene (HDPE) and polytetrafluoroethylene (PTFE), operating in a THz window from 395 to 455 GHz. The numerical results allowed us to characterize the relation between the reflectance\/transmittance and the amount of force required to obtain a specific frequency shift along that window. It was found that the device assembled with HDPE presents a more linear response and it is able to pass from a full transparency to almost full opacity using only its linear operating zone. Due to its characteristics, this THz filter might be an interesting solution not only for THz sensors based on reconfigurable filters but also for optical modulators for the THz domain.<\/jats:p>","DOI":"10.3390\/photonics7030048","type":"journal-article","created":{"date-parts":[[2020,7,14]],"date-time":"2020-07-14T04:46:01Z","timestamp":1594701961000},"page":"48","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Design of a Reconfigurable THz Filter Based on Metamaterial Wire Resonators with Applications on Sensor Devices"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4759-4817","authenticated-orcid":false,"given":"Jo\u00e3o Pedro","family":"Pavia","sequence":"first","affiliation":[{"name":"Department of Information Science and Technology, ISCTE\u2014Instituto Universit\u00e1rio de Lisboa, Av. das For\u00e7as Armadas, 1649-026 Lisbon, Portugal"},{"name":"Radio Systems Group, Instituto de Telecomunica\u00e7\u00f5es, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3823-4470","authenticated-orcid":false,"given":"Nuno","family":"Souto","sequence":"additional","affiliation":[{"name":"Department of Information Science and Technology, ISCTE\u2014Instituto Universit\u00e1rio de Lisboa, Av. das For\u00e7as Armadas, 1649-026 Lisbon, Portugal"},{"name":"Radio Systems Group, Instituto de Telecomunica\u00e7\u00f5es, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6071-6479","authenticated-orcid":false,"given":"Marco Alexandre","family":"Ribeiro","sequence":"additional","affiliation":[{"name":"Department of Information Science and Technology, ISCTE\u2014Instituto Universit\u00e1rio de Lisboa, Av. das For\u00e7as Armadas, 1649-026 Lisbon, Portugal"},{"name":"Radio Systems Group, Instituto de Telecomunica\u00e7\u00f5es, Av. Rovisco Pais, 1049-001 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"13864","DOI":"10.1039\/C7NR03824K","article-title":"Mechanisms and applications of terahertz metamaterial sensing: A review","volume":"9","author":"Xu","year":"2017","journal-title":"Nanoscale"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Salim, A., and Lim, S. (2018). Review of Recent Metamaterial Microfluidic Sensors. Sensors, 18.","DOI":"10.3390\/s18010232"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"161405","DOI":"10.1103\/PhysRevB.97.161405","article-title":"Tunable plasmonic toroidal terahertz metamodulator","volume":"97","author":"Gerislioglu","year":"2018","journal-title":"Phys. Rev. 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