{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T13:36:53Z","timestamp":1777469813745,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,21]],"date-time":"2023-03-21T00:00:00Z","timestamp":1679356800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Fund Denmark","award":["9040-00360B"],"award-info":[{"award-number":["9040-00360B"]}]},{"DOI":"10.13039\/100012774","name":"Innovation Fund Denmark","doi-asserted-by":"crossref","award":["9040-00360B"],"award-info":[{"award-number":["9040-00360B"]}],"id":[{"id":"10.13039\/100012774","id-type":"DOI","asserted-by":"crossref"}]},{"name":"DTU Elektro","award":["9040-00360B"],"award-info":[{"award-number":["9040-00360B"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Sensors"],"abstract":"<jats:p>We demonstrate the use of a novel, integrated THz system to obtain time-domain signals for spectroscopy in the 0.1\u20131.4 THz range. The system employs THz generation in a photomixing antenna excited by a broadband amplified spontaneous emission (ASE) light source and THz detection with a photoconductive antenna by coherent cross-correlation sampling. We benchmark the performance of our system against a state-of-the-art femtosecond-based THz time-domain spectroscopy system in terms of mapping and imaging of the sheet conductivity of large-area graphene grown by chemical vapor deposition (CVD) and transferred to a PET polymer substrate. We propose to integrate the algorithm for the extraction of the sheet conductivity with the data acquisition, thereby enabling true in-line monitoring capability of the system for integration in graphene production facilities.<\/jats:p>","DOI":"10.3390\/s23063297","type":"journal-article","created":{"date-parts":[[2023,3,21]],"date-time":"2023-03-21T02:36:22Z","timestamp":1679366182000},"page":"3297","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Terahertz Cross-Correlation Spectroscopy and Imaging of Large-Area Graphene"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2744-9233","authenticated-orcid":false,"given":"Bj\u00f8rn H\u00fcbschmann","family":"M\u00f8lvig","sequence":"first","affiliation":[{"name":"Department of Electrical and Photonics Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5272-7031","authenticated-orcid":false,"given":"Thorsten","family":"B\u00e6k","sequence":"additional","affiliation":[{"name":"Department of Electrical and Photonics Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"},{"name":"GLAZE Technologies Aps, 2950 Vedb\u00e6k, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jie","family":"Ji","sequence":"additional","affiliation":[{"name":"Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"B\u00f8ggild","sequence":"additional","affiliation":[{"name":"Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9456-9331","authenticated-orcid":false,"given":"Simon Jappe","family":"Lange","sequence":"additional","affiliation":[{"name":"Department of Electrical and Photonics Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark"},{"name":"GLAZE Technologies Aps, 2950 Vedb\u00e6k, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"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"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"666","DOI":"10.1126\/science.1102896","article-title":"Electric Field Effect in Atomically Thin Carbon Films","volume":"306","author":"Novoselov","year":"2004","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1103\/RevModPhys.81.109","article-title":"The electronic properties of graphene","volume":"81","author":"Guinea","year":"2009","journal-title":"Rev. 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