Dynamics of a Holstein polaron with off-diagonal coupling
Dynamics of a one-dimensional Holstein polaron with off-diagonal exciton-phonon coupling is studied by employing the Dirac-Frenkel time-dependent variational principle. The trial state used is the Davydov D2 Ansatz with two sets of variational parameters, one for each constituting particle in the li...
| Main Authors: | , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2013
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| Online Access: | https://hdl.handle.net/10356/95040 http://hdl.handle.net/10220/9401 |
| _version_ | 1811695822998339584 |
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| author | Zhao, Yang Luo, Bin Zhang, Yuyu Ye, Jun |
| author2 | School of Materials Science & Engineering |
| author_facet | School of Materials Science & Engineering Zhao, Yang Luo, Bin Zhang, Yuyu Ye, Jun |
| author_sort | Zhao, Yang |
| collection | NTU |
| description | Dynamics of a one-dimensional Holstein polaron with off-diagonal exciton-phonon coupling is studied by employing the Dirac-Frenkel time-dependent variational principle. The trial state used is the Davydov D2 Ansatz with two sets of variational parameters, one for each constituting particle in the linearly coupled exciton-phonon system. Validity of the approach is carefully checked by quantifying how faithfully the trial state follows the Schrödinger equation. A close examination of variational outputs reveals fine details of polaron dynamics and intricacies of dynamic exciton-phonon correlations. In the absence of diagonal coupling, the change in the polaron effective mass hinges on the sign of the transfer integral due to the antisymmetric nature of the off-diagonal coupling. The role of the off-diagonal coupling switches from being an agent of transport at moderate coupling strengths to that of localization at large coupling strengths. Increasing the phonon bandwidth leads to a reduced polaron effective mass at the zone center and an overall lowering of the polaron band. |
| first_indexed | 2024-10-01T07:29:35Z |
| format | Journal Article |
| id | ntu-10356/95040 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T07:29:35Z |
| publishDate | 2013 |
| record_format | dspace |
| spelling | ntu-10356/950402023-07-14T15:57:26Z Dynamics of a Holstein polaron with off-diagonal coupling Zhao, Yang Luo, Bin Zhang, Yuyu Ye, Jun School of Materials Science & Engineering Dynamics of a one-dimensional Holstein polaron with off-diagonal exciton-phonon coupling is studied by employing the Dirac-Frenkel time-dependent variational principle. The trial state used is the Davydov D2 Ansatz with two sets of variational parameters, one for each constituting particle in the linearly coupled exciton-phonon system. Validity of the approach is carefully checked by quantifying how faithfully the trial state follows the Schrödinger equation. A close examination of variational outputs reveals fine details of polaron dynamics and intricacies of dynamic exciton-phonon correlations. In the absence of diagonal coupling, the change in the polaron effective mass hinges on the sign of the transfer integral due to the antisymmetric nature of the off-diagonal coupling. The role of the off-diagonal coupling switches from being an agent of transport at moderate coupling strengths to that of localization at large coupling strengths. Increasing the phonon bandwidth leads to a reduced polaron effective mass at the zone center and an overall lowering of the polaron band. Published version 2013-03-13T08:33:05Z 2019-12-06T19:07:04Z 2013-03-13T08:33:05Z 2019-12-06T19:07:04Z 2012 2012 Journal Article Zhao, Y., Luo, B., Zhang, Y., & Ye, J. (2012). Dynamics of a Holstein polaron with off-diagonal coupling. The Journal of Chemical Physics, 137(8). 0021-9606 https://hdl.handle.net/10356/95040 http://hdl.handle.net/10220/9401 10.1063/1.4748140 en The Journal of Chemical Physics © 2012 American Institute of Physics. This paper was published in The Journal of Chemical Physics and is made available as an electronic reprint (preprint) with permission of American Institute of Physics. The paper can be found at the following official DOI: [http://dx.doi.org/10.1063/1.4748140]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law. application/pdf |
| spellingShingle | Zhao, Yang Luo, Bin Zhang, Yuyu Ye, Jun Dynamics of a Holstein polaron with off-diagonal coupling |
| title | Dynamics of a Holstein polaron with off-diagonal coupling |
| title_full | Dynamics of a Holstein polaron with off-diagonal coupling |
| title_fullStr | Dynamics of a Holstein polaron with off-diagonal coupling |
| title_full_unstemmed | Dynamics of a Holstein polaron with off-diagonal coupling |
| title_short | Dynamics of a Holstein polaron with off-diagonal coupling |
| title_sort | dynamics of a holstein polaron with off diagonal coupling |
| url | https://hdl.handle.net/10356/95040 http://hdl.handle.net/10220/9401 |
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