Towards quantitative accuracy in first-principles transport calculations: The GW method applied to alkane/gold junctions
The calculation of the electronic conductance of nanoscale junctions from first principles is a long-standing problem in the field of charge transport. Here we demonstrate excellent agreement with experiments for the transport properties of the gold/alkanediamine benchmark system when electron–elect...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Beilstein-Institut
2011-11-01
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| Series: | Beilstein Journal of Nanotechnology |
| Subjects: | |
| Online Access: | https://doi.org/10.3762/bjnano.2.82 |
| _version_ | 1819096987772911616 |
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| author | Mikkel Strange Kristian S. Thygesen |
| author_facet | Mikkel Strange Kristian S. Thygesen |
| author_sort | Mikkel Strange |
| collection | DOAJ |
| description | The calculation of the electronic conductance of nanoscale junctions from first principles is a long-standing problem in the field of charge transport. Here we demonstrate excellent agreement with experiments for the transport properties of the gold/alkanediamine benchmark system when electron–electron interactions are described by the many-body GW approximation. The conductance follows an exponential length dependence: Gn = Gc exp(−βn). The main difference from standard density functional theory (DFT) calculations is a significant reduction of the contact conductance, Gc, due to an improved alignment of the molecular energy levels with the metal Fermi energy. The molecular orbitals involved in the tunneling process comprise states delocalized over the carbon backbone and states localized on the amine end groups. We find that dynamic screening effects renormalize the two types of states in qualitatively different ways when the molecule is inserted in the junction. Consequently, the GW transport results cannot be mimicked by DFT calculations employing a simple scissors operator. |
| first_indexed | 2024-12-22T00:07:56Z |
| format | Article |
| id | doaj.art-9923121050eb4872a37b7073bb3b40a7 |
| institution | Directory Open Access Journal |
| issn | 2190-4286 |
| language | English |
| last_indexed | 2024-12-22T00:07:56Z |
| publishDate | 2011-11-01 |
| publisher | Beilstein-Institut |
| record_format | Article |
| series | Beilstein Journal of Nanotechnology |
| spelling | doaj.art-9923121050eb4872a37b7073bb3b40a72022-12-21T18:45:30ZengBeilstein-InstitutBeilstein Journal of Nanotechnology2190-42862011-11-012174675410.3762/bjnano.2.822190-4286-2-82Towards quantitative accuracy in first-principles transport calculations: The GW method applied to alkane/gold junctionsMikkel Strange0Kristian S. Thygesen1Center for Atomic-scale Materials Design, Department of Physics Technical University of Denmark, DK - 2800 Kgs. Lyngby, DenmarkCenter for Atomic-scale Materials Design, Department of Physics Technical University of Denmark, DK - 2800 Kgs. Lyngby, DenmarkThe calculation of the electronic conductance of nanoscale junctions from first principles is a long-standing problem in the field of charge transport. Here we demonstrate excellent agreement with experiments for the transport properties of the gold/alkanediamine benchmark system when electron–electron interactions are described by the many-body GW approximation. The conductance follows an exponential length dependence: Gn = Gc exp(−βn). The main difference from standard density functional theory (DFT) calculations is a significant reduction of the contact conductance, Gc, due to an improved alignment of the molecular energy levels with the metal Fermi energy. The molecular orbitals involved in the tunneling process comprise states delocalized over the carbon backbone and states localized on the amine end groups. We find that dynamic screening effects renormalize the two types of states in qualitatively different ways when the molecule is inserted in the junction. Consequently, the GW transport results cannot be mimicked by DFT calculations employing a simple scissors operator.https://doi.org/10.3762/bjnano.2.82alkanesdensity functional theoryelectron transportgold junctionGW |
| spellingShingle | Mikkel Strange Kristian S. Thygesen Towards quantitative accuracy in first-principles transport calculations: The GW method applied to alkane/gold junctions Beilstein Journal of Nanotechnology alkanes density functional theory electron transport gold junction GW |
| title | Towards quantitative accuracy in first-principles transport calculations: The GW method applied to alkane/gold junctions |
| title_full | Towards quantitative accuracy in first-principles transport calculations: The GW method applied to alkane/gold junctions |
| title_fullStr | Towards quantitative accuracy in first-principles transport calculations: The GW method applied to alkane/gold junctions |
| title_full_unstemmed | Towards quantitative accuracy in first-principles transport calculations: The GW method applied to alkane/gold junctions |
| title_short | Towards quantitative accuracy in first-principles transport calculations: The GW method applied to alkane/gold junctions |
| title_sort | towards quantitative accuracy in first principles transport calculations the gw method applied to alkane gold junctions |
| topic | alkanes density functional theory electron transport gold junction GW |
| url | https://doi.org/10.3762/bjnano.2.82 |
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