{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T20:39:03Z","timestamp":1774384743601,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,2,10]],"date-time":"2018-02-10T00:00:00Z","timestamp":1518220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Spanish Ministry of Economy and Commerce\/ERDF","award":["TEC2015-65477-R"],"award-info":[{"award-number":["TEC2015-65477-R"]}]},{"name":"Junta de Castilla y Le\u00f3n\/ERDF","award":["SA045U16"],"award-info":[{"award-number":["SA045U16"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Plasma waves in gated 2-D systems can be used to efficiently detect THz electromagnetic radiation. Solid-state plasma wave-based sensors can be used as detectors in THz imaging systems. An experimental study of the sub-THz response of II-gate strained-Si Schottky-gated MODFETs (Modulation-doped Field-Effect Transistor) was performed. The response of the strained-Si MODFET has been characterized at two frequencies: 150 and 300 GHz: The DC drain-to-source voltage transducing the THz radiation (photovoltaic mode) of 250-nm gate length transistors exhibited a non-resonant response that agrees with theoretical models and physics-based simulations of the electrical response of the transistor. When imposing a weak source-to-drain current of 5 \u03bcA, a substantial increase of the photoresponse was found. This increase is translated into an enhancement of the responsivity by one order of magnitude as compared to the photovoltaic mode, while the NEP (Noise Equivalent Power) is reduced in the subthreshold region. Strained-Si MODFETs demonstrated an excellent performance as detectors in THz imaging.<\/jats:p>","DOI":"10.3390\/s18020543","type":"journal-article","created":{"date-parts":[[2018,2,12]],"date-time":"2018-02-12T10:50:38Z","timestamp":1518432638000},"page":"543","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Sub-THz Imaging Using Non-Resonant HEMT Detectors"],"prefix":"10.3390","volume":"18","author":[{"given":"Juan","family":"Delgado-Notario","sequence":"first","affiliation":[{"name":"Nano Lab, Salamanca University, Salamanca 37008, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6555-9871","authenticated-orcid":false,"given":"Jesus","family":"Velazquez-Perez","sequence":"additional","affiliation":[{"name":"Nano Lab, Salamanca University, Salamanca 37008, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yahya","family":"Meziani","sequence":"additional","affiliation":[{"name":"Nano Lab, Salamanca University, Salamanca 37008, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kristel","family":"Fobelets","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Imperial College, South Kensington Campus, London SW7 2AZ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,2,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Rainsford, T., Mickan, S.P., and Abbott, D. 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