{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:02:12Z","timestamp":1760148132187,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,3,31]],"date-time":"2023-03-31T00:00:00Z","timestamp":1680220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100008397","name":"Velux Fonden","doi-asserted-by":"publisher","award":["00023215","2035-00365B","9040-00360B"],"award-info":[{"award-number":["00023215","2035-00365B","9040-00360B"]}],"id":[{"id":"10.13039\/100008397","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Independent Research Fund Denmark","award":["00023215","2035-00365B","9040-00360B"],"award-info":[{"award-number":["00023215","2035-00365B","9040-00360B"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We demonstrate that the conductivity of graphene on thin-film polymer substrates can be accurately determined by reflection-mode air-plasma-based THz time-domain spectroscopy (THz-TDS). The phase uncertainty issue associated with reflection measurements is discussed, and our implementation is validated by convincing agreement with graphene electrical properties extracted from more conventional transmission-mode measurements. Both the reflection and transmission THz-TDS measurements reveal strong non-linear and instantaneous conductivity depletion across an ultra-broad bandwidth (1\u20139 THz) under relatively high incident THz electrical field strengths (up to 1050 kV\/cm).<\/jats:p>","DOI":"10.3390\/s23073669","type":"journal-article","created":{"date-parts":[[2023,4,3]],"date-time":"2023-04-03T02:32:27Z","timestamp":1680489147000},"page":"3669","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Non-Linear Conductivity Response of Graphene on Thin-Film PET Characterized by Transmission and Reflection Air-Plasma THz-TDS"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4528-5447","authenticated-orcid":false,"given":"Binbin","family":"Zhou","sequence":"first","affiliation":[{"name":"Department of Electrical and Photonics Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3405-6075","authenticated-orcid":false,"given":"Mattias","family":"Rasmussen","sequence":"additional","affiliation":[{"name":"Department of Electrical and Photonics Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}]},{"given":"Patrick Rebsdorf","family":"Whelan","sequence":"additional","affiliation":[{"name":"Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}]},{"given":"Jie","family":"Ji","sequence":"additional","affiliation":[{"name":"Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5152-0327","authenticated-orcid":false,"given":"Abhay","family":"Shivayogimath","sequence":"additional","affiliation":[{"name":"Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4342-0449","authenticated-orcid":false,"given":"Peter","family":"B\u00f8ggild","sequence":"additional","affiliation":[{"name":"Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3915-1167","authenticated-orcid":false,"given":"Peter Uhd","family":"Jepsen","sequence":"additional","affiliation":[{"name":"Department of Electrical and Photonics Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1312","DOI":"10.1126\/science.1171245","article-title":"Large-area synthesis of high-quality and uniform graphene films on copper foils","volume":"324","author":"Li","year":"2009","journal-title":"Sciences"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"10369","DOI":"10.1021\/acsami.8b00846","article-title":"A scalable route to nanoporous large-area atomically thin graphene membranes by roll-to-roll chemical vapor deposition and polymer support casting","volume":"10","author":"Kidambi","year":"2018","journal-title":"ACS Appl. 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