Visualizing Orbital Content of Electronic Bands in Anisotropic 2D Semiconducting ReSe$_{2}$
| Autor: | Luca Moreschini, Aaron Bostwick, Hyeonsik Cheong, Eli Rotenberg, Surani M. Gunasekera, Ji Seop Oh, Ji-Ho Kim, In-Whan Lyo, Seung-Hyun Chun, Chris Jozwiak, Young Jun Chang, Byoung Ki Choi, Soo Yeon Lim, Marcin Mucha-Kruczynski, Søren Ulstrup |
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| Rok vydání: | 2020 |
| Předmět: |
Materials science
Band gap Photoemission spectroscopy Scanning tunneling spectroscopy orbital-selective electronic structure General Physics and Astronomy FOS: Physical sciences 02 engineering and technology Electronic structure 010402 general chemistry 01 natural sciences rhenium diselenide Mesoscale and Nanoscale Physics (cond-mat.mes-hall) General Materials Science two-dimensional materials Nanoscience & Nanotechnology Electronic band structure Condensed Matter - Materials Science Condensed matter physics Condensed Matter - Mesoscale and Nanoscale Physics business.industry Doping transition metal dichalcogenides General Engineering anisotropic 2D semiconductor Materials Science (cond-mat.mtrl-sci) 021001 nanoscience & nanotechnology 0104 chemical sciences Semiconductor Density functional theory 0210 nano-technology business |
| Zdroj: | ACS nano, vol 14, iss 7 Choi, B K, Ulstrup, S, Gunasekera, S M, Kim, J, Lim, S Y, Moreschini, L, Oh, J S, Chun, S, Jozwiak, C, Bostwick, A, Rotenberg, E, Cheong, H, Lyo, I, Mucha-Kruczynski, M & Chang, Y J 2020, ' Visualizing Orbital Content of Electronic Bands in Anisotropic 2D Semiconducting ReSe2 ', ACS Nano, vol. 14, no. 7, pp. 7880-7891 . https://doi.org/10.1021/acsnano.0c01054 Choi, B K, Ulstrup, S, Gunasekera, S M, Kim, J, Lim, S Y, Moreschini, L, Oh, J S, Chun, S H, Jozwiak, C, Bostwick, A, Rotenberg, E, Cheong, H, Lyo, I W, Mucha-Kruczynski, M & Chang, Y J 2020, ' Visualizing Orbital Content of Electronic Bands in Anisotropic 2D Semiconducting ReSe 2 ', ACS Nano, vol. 14, no. 7, pp. 7880-7891 . https://doi.org/10.1021/acsnano.0c01054 |
| DOI: | 10.48550/arxiv.2005.14525 |
| Popis: | Many properties of layered materials change as they are thinned from their bulk forms down to single layers, with examples including indirect-to-direct band gap transition in 2H semiconducting transition metal dichalcogenides as well as thickness-dependent changes in the valence band structure in post-transition metal monochalcogenides and black phosphorus. Here, we use angle-resolved photoemission spectroscopy to study the electronic band structure of monolayer ReSe$_{2}$, a semiconductor with a distorted 1T structure and in-plane anisotropy. By changing the polarization of incoming photons, we demonstrate that for ReSe$_{2}$, in contrast to the 2H materials, the out-of-plane transition metal $d_{z^{2}}$ and chalcogen $p_{z}$ orbitals do not contribute significantly to the top of the valence band which explains the reported weak changes in the electronic structure of this compound as a function of layer number. We estimate a band gap of 1.7 eV in pristine ReSe$_{2}$ using scanning tunneling spectroscopy and explore the implications on the gap following surface-doping with potassium. A lower bound of 1.4 eV is estimated for the gap in the fully doped case, suggesting that doping-dependent many-body effects significantly affect the electronic properties of ReSe$_{2}$. Our results, supported by density functional theory calculations, provide insight into the mechanisms behind polarization-dependent optical properties of rhenium dichalcogenides and highlight their place amongst two-dimensional crystals. Comment: 37 pages (including Supporting Information), 7 figures in the main text |
| Databáze: | OpenAIRE |
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