{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T19:35:31Z","timestamp":1768937731915,"version":"3.49.0"},"reference-count":62,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T00:00:00Z","timestamp":1768608000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science and technology council","award":["NSTC-110-2112-M-007-038"],"award-info":[{"award-number":["NSTC-110-2112-M-007-038"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Valley-dependent topological physics offers a promising avenue for designing nanoscale devices based on gapless single-layer graphene. To demonstrate this potential, we investigate an electrical bias-controlled topological discontinuity in valley polarization within a two-segment armchair nanoribbon of gapless single-layer graphene. This discontinuity is created at the interface by applying opposite in-plane, transverse electrical biases to the two segments. An efficient tight-binding theoretical formulation is developed to calculate electron states in the structure. In a reference configuration, we obtain energy eigenvalues and probability distributions that feature interface-confined electron eigenstates induced by the topological discontinuity. Moreover, to elucidate the implications of interface confinement for electron transport, a modified configuration is introduced to transform the eigenstates into transport-active, quasi-localized ones. We show that such states result in Fano \u201canti-resonances\u201d in transmission spectra. The resilience of these quasi-localized states and their associated Fano fingerprints is examined with respect to fluctuations. Finally, a proof-of-concept band-stop electron energy filter is presented, highlighting the potential of this confinement mechanism and, more broadly, valley-dependent topological physics in designing nanoscale devices in gapless single-layer graphene.<\/jats:p>","DOI":"10.3390\/ma19020380","type":"journal-article","created":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T11:35:27Z","timestamp":1768822527000},"page":"380","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Valley-Dependent Topological Interface States in Biased Armchair Nanoribbons of Gapless Single-Layer Graphene for Transport Applications"],"prefix":"10.3390","volume":"19","author":[{"given":"Zheng-Han","family":"Huang","sequence":"first","affiliation":[{"name":"Institute of Electronic Engineering, National Tsing-Hua University, Hsin-Chu 30013, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-0818-985X","authenticated-orcid":false,"given":"Jing-Yuan","family":"Lai","sequence":"additional","affiliation":[{"name":"College of Semiconductor Research, National Tsing-Hua University, Hsin-Chu 30013, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5160-9789","authenticated-orcid":false,"given":"Yu-Shu","family":"Wu","sequence":"additional","affiliation":[{"name":"Institute of Electronic Engineering, National Tsing-Hua University, Hsin-Chu 30013, Taiwan"},{"name":"College of Semiconductor Research, National Tsing-Hua University, Hsin-Chu 30013, Taiwan"},{"name":"Department of Physics, National Tsing-Hua University, Hsin-Chu 30013, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,17]]},"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":"201","DOI":"10.1038\/nature04235","article-title":"Experimental Observation of the Quantum Hall Effect and Berry\u2019s Phase in Graphene","volume":"438","author":"Zhang","year":"2005","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1038\/nmat1849","article-title":"The Rise of Graphene","volume":"6","author":"Geim","year":"2007","journal-title":"Nat. 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