{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T01:34:10Z","timestamp":1777512850699,"version":"3.51.4"},"reference-count":47,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,12,30]],"date-time":"2023-12-30T00:00:00Z","timestamp":1703894400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fit4MedRob \u2013 Fit for Medical Robotics","award":["PNC0000007"],"award-info":[{"award-number":["PNC0000007"]}]},{"name":"Hybrid 3D Chiral Metamaterial\/2D MoS2 Phototransistors for Circularly Polarized Light Detection (HYSPID)","award":["B86C18000430006"],"award-info":[{"award-number":["B86C18000430006"]}]},{"name":"Nano Foundries and Fine Analysis - Digital Infrastructure (NFFA-DI)","award":["B53C22004310006"],"award-info":[{"award-number":["B53C22004310006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>MoS2 is a two-dimensional layered transition metal dichalcogenide with unique electronic and optical properties. The fabrication of ultrathin MoS2 is vitally important, since interlayer interactions in its ultrathin varieties will become thickness-dependent, providing thickness-governed tunability and diverse applications of those properties. Unlike with a number of studies that have reported detailed information on direct bandgap emission from MoS2 monolayers, reliable experimental evidence for thickness-induced evolution or transformation of the indirect bandgap remains scarce. Here, the sulfurization of MoO3 thin films with nominal thicknesses of 30 nm, 5 nm and 3 nm was performed. All sulfurized samples were examined at room temperature with spectroscopic ellipsometry and photoluminescence spectroscopy to obtain information about their dielectric function and edge emission spectra. This investigation unveiled an indirect-to-indirect crossover between the transitions, associated with two different \u039b and K valleys of the MoS2 conduction band, by thinning its thickness down to a few layers.<\/jats:p>","DOI":"10.3390\/nano14010096","type":"journal-article","created":{"date-parts":[[2023,12,31]],"date-time":"2023-12-31T10:01:06Z","timestamp":1704016866000},"page":"96","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Two-Channel Indirect-Gap Photoluminescence and Competition between the Conduction Band Valleys in Few-Layer MoS2"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8122-4721","authenticated-orcid":false,"given":"Ayaz H.","family":"Bayramov","sequence":"first","affiliation":[{"name":"Institute of Physics, Ministry of Science and Education, Baku Az1143, Azerbaijan"}]},{"given":"Elnur A.","family":"Bagiyev","sequence":"additional","affiliation":[{"name":"Institute of Physics, Ministry of Science and Education, Baku Az1143, Azerbaijan"}]},{"given":"Elvin H.","family":"Alizade","sequence":"additional","affiliation":[{"name":"Institute of Physics, Ministry of Science and Education, Baku Az1143, Azerbaijan"}]},{"given":"Javid N.","family":"Jalilli","sequence":"additional","affiliation":[{"name":"Institute of Physics, Ministry of Science and Education, Baku Az1143, Azerbaijan"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-4302-1913","authenticated-orcid":false,"given":"Nazim T.","family":"Mamedov","sequence":"additional","affiliation":[{"name":"Institute of Physics, Ministry of Science and Education, Baku Az1143, Azerbaijan"},{"name":"Institute of Physical Problems, Baku State University, Ministry of Science and Education, Baku Az1148, Azerbaijan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5915-1143","authenticated-orcid":false,"given":"Zakir A.","family":"Jahangirli","sequence":"additional","affiliation":[{"name":"Institute of Physics, Ministry of Science and Education, Baku Az1143, Azerbaijan"},{"name":"Institute of Physical Problems, Baku State University, Ministry of Science and Education, Baku Az1148, Azerbaijan"}]},{"given":"Saida G.","family":"Asadullayeva","sequence":"additional","affiliation":[{"name":"Institute of Physics, Ministry of Science and Education, Baku Az1143, Azerbaijan"}]},{"given":"Yegana N.","family":"Aliyeva","sequence":"additional","affiliation":[{"name":"Institute of Physical Problems, Baku State University, Ministry of Science and Education, Baku Az1148, Azerbaijan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4934-3376","authenticated-orcid":false,"given":"Massimo","family":"Cuscun\u00e0","sequence":"additional","affiliation":[{"name":"National Research Council, Institute of Nanotechnology (NANOTEC), University c\/o Campus Ecotekne, Via per Monteroni, 73100 Lecce, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-8121-2941","authenticated-orcid":false,"given":"Daniela","family":"Lorenzo","sequence":"additional","affiliation":[{"name":"National Research Council, Institute of Nanotechnology (NANOTEC), University c\/o Campus Ecotekne, Via per Monteroni, 73100 Lecce, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8170-6694","authenticated-orcid":false,"given":"Marco","family":"Esposito","sequence":"additional","affiliation":[{"name":"National Research Council, Institute of Nanotechnology (NANOTEC), University c\/o Campus Ecotekne, Via per Monteroni, 73100 Lecce, Italy"}]},{"given":"Gianluca","family":"Balestra","sequence":"additional","affiliation":[{"name":"National Research Council, Institute of Nanotechnology (NANOTEC), University c\/o Campus Ecotekne, Via per Monteroni, 73100 Lecce, Italy"},{"name":"Department of Mathematics and Physics \u2018\u2018Ennio De Giorgi\u201d, University of Salento, c\/o Campus Ecotekne, Via per Monteroni, 73100 Lecce, Italy"}]},{"given":"Daniela","family":"Simeone","sequence":"additional","affiliation":[{"name":"National Research Council, Institute of Nanotechnology (NANOTEC), University c\/o Campus Ecotekne, Via per Monteroni, 73100 Lecce, Italy"}]},{"given":"David Maria","family":"Tobaldi","sequence":"additional","affiliation":[{"name":"National Research Council, Institute of Nanotechnology (NANOTEC), University c\/o Campus Ecotekne, Via per Monteroni, 73100 Lecce, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3063-922X","authenticated-orcid":false,"given":"Daniel","family":"Abou-Ras","sequence":"additional","affiliation":[{"name":"Helmholtz-Zentrum Berlin for Materials and Energy (HZB), Department of Structure and Dynamics of Energy Materials, 14109 Berlin, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6687-614X","authenticated-orcid":false,"given":"Susan","family":"Schorr","sequence":"additional","affiliation":[{"name":"Helmholtz-Zentrum Berlin for Materials and Energy (HZB), Department of Structure and Dynamics of Energy Materials, 14109 Berlin, Germany"},{"name":"Institute of Geological Sciences, Free University of Berlin, 14195 Berlin, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"245213","DOI":"10.1103\/PhysRevB.83.245213","article-title":"Influence of quantum confinement on the electronic structure of the transition metal sulfide TS2","volume":"83","author":"Kuc","year":"2011","journal-title":"Phys. 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