{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T22:21:59Z","timestamp":1782858119826,"version":"3.54.5"},"reference-count":33,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,22]],"date-time":"2022-01-22T00:00:00Z","timestamp":1642809600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003447","name":"State Scholarships Foundation","doi-asserted-by":"publisher","award":["2019-050-0503-17343"],"award-info":[{"award-number":["2019-050-0503-17343"]}],"id":[{"id":"10.13039\/501100003447","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Axioms"],"abstract":"<jats:p>The accurate modeling of curved graphene layers for time-domain electromagnetic simulations is discussed in the present work. Initially, the advanced properties of graphene are presented, focusing on the propagation of strongly confined surface plasmon polariton waves at the far-infrared regime. Then, the implementation of an unstructured triangular grid was examined, based on the Delaunay triangulation method. The electric-field components were placed at the edges of the triangles, while two different techniques were proposed for the sampling of the magnetic ones. Specifically, the first one suggests that the magnetic component is placed at the triangle\u2019s circumcenter providing more accurate results, although instability may occur for nonacute triangles. On the other hand, the magnetic field was sampled at the triangle\u2019s centroid, considering the second technique, ensuring the algorithm\u2019s stability, but further approximations were required, leading to a slight accuracy reduction. Moreover, the updating equations in the time-domain were extracted via an appropriate approximation of Maxwell equations in their integral form. Finally, graphene was introduced in the computational domain as an equivalent surface current density, whose location matches the corresponding electric components. The validity of our methodology was successfully performed via the comparison of graphene surface wave propagation properties to their theoretical values, whereas the global error determination indicates the minimal triangle dimensions. Additionally, an instructive setup comprising a circular graphene scatterer was analyzed thoroughly, to reveal our technique\u2019s advantages compared to the conventional staircase discretization.<\/jats:p>","DOI":"10.3390\/axioms11020044","type":"journal-article","created":{"date-parts":[[2022,1,23]],"date-time":"2022-01-23T20:32:52Z","timestamp":1642969972000},"page":"44","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Accurate Time-Domain Modeling of Arbitrarily Shaped Graphene Layers Utilizing Unstructured Triangular Grids"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1295-4613","authenticated-orcid":false,"given":"Stamatios","family":"Amanatiadis","sequence":"first","affiliation":[{"name":"Department of Electrical & Computer Engineering, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6194-8100","authenticated-orcid":false,"given":"Theodoros","family":"Zygiridis","sequence":"additional","affiliation":[{"name":"Department of Electrical & Computer Engineering, University of Western Macedonia, GR-50100 Kozani, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0959-7838","authenticated-orcid":false,"given":"Nikolaos","family":"Kantartzis","sequence":"additional","affiliation":[{"name":"Department of Electrical & Computer Engineering, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,22]]},"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":"016803","DOI":"10.1103\/PhysRevLett.99.016803","article-title":"New electromagnetic mode in graphene","volume":"99","author":"Mikhailov","year":"2007","journal-title":"Phys. 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