Optimal power generation using dark states in dimers strongly coupled to their environment
Dark state protection has been proposed as a mechanism to increase the power output of light harvesting devices by reducing the rate of radiative recombination. Indeed many theoretical studies have reported increased power outputs in dimer systems which use quantum interference to generate dark stat...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2019-01-01
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| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/ab25ca |
| _version_ | 1797750065120411648 |
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| author | D M Rouse E M Gauger B W Lovett |
| author_facet | D M Rouse E M Gauger B W Lovett |
| author_sort | D M Rouse |
| collection | DOAJ |
| description | Dark state protection has been proposed as a mechanism to increase the power output of light harvesting devices by reducing the rate of radiative recombination. Indeed many theoretical studies have reported increased power outputs in dimer systems which use quantum interference to generate dark states. These models have typically been restricted to particular geometries and to weakly coupled vibrational baths. Here we consider the experimentally-relevant strong vibrational coupling regime with no geometric restrictions on the dimer. We analyze how dark states can be formed in the dimer by numerically minimizing the emission rate of the lowest energy excited eigenstate, and then calculate the power output of the molecules with these dark states. We find that there are two distinct types of dark states depending on whether the monomers form homodimers, where energy splittings and dipole strengths are identical, or heterodimers, where there is some difference. Homodimers, which exploit destructive quantum interference, produce high power outputs but strong phonon couplings and perturbations from ideal geometries are extremely detrimental. Heterodimers, which are closer to the classical picture of a distinct donor and acceptor molecule, produce an intermediate power output that is relatively stable to these changes. The strong vibrational couplings typically found in organic molecules will suppress destructive interference and thus favor the dark-state enhancement offered by heterodimers. |
| first_indexed | 2024-03-12T16:28:19Z |
| format | Article |
| id | doaj.art-49dce56bad2b42819de03627e5e50e89 |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:28:19Z |
| publishDate | 2019-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-49dce56bad2b42819de03627e5e50e892023-08-08T15:38:08ZengIOP PublishingNew Journal of Physics1367-26302019-01-0121606302510.1088/1367-2630/ab25caOptimal power generation using dark states in dimers strongly coupled to their environmentD M Rouse0https://orcid.org/0000-0002-7205-0483E M Gauger1https://orcid.org/0000-0003-1232-9885B W Lovett2https://orcid.org/0000-0001-5142-9585SUPA, School of Physics and Astronomy, University of St. Andrews , St. Andrews KY16 9SS, United KingdomSUPA, Institute of Photonics and Quantum Sciences, Heriot-Watt University , Edinburgh EH14 4AS, United KingdomSUPA, School of Physics and Astronomy, University of St. Andrews , St. Andrews KY16 9SS, United KingdomDark state protection has been proposed as a mechanism to increase the power output of light harvesting devices by reducing the rate of radiative recombination. Indeed many theoretical studies have reported increased power outputs in dimer systems which use quantum interference to generate dark states. These models have typically been restricted to particular geometries and to weakly coupled vibrational baths. Here we consider the experimentally-relevant strong vibrational coupling regime with no geometric restrictions on the dimer. We analyze how dark states can be formed in the dimer by numerically minimizing the emission rate of the lowest energy excited eigenstate, and then calculate the power output of the molecules with these dark states. We find that there are two distinct types of dark states depending on whether the monomers form homodimers, where energy splittings and dipole strengths are identical, or heterodimers, where there is some difference. Homodimers, which exploit destructive quantum interference, produce high power outputs but strong phonon couplings and perturbations from ideal geometries are extremely detrimental. Heterodimers, which are closer to the classical picture of a distinct donor and acceptor molecule, produce an intermediate power output that is relatively stable to these changes. The strong vibrational couplings typically found in organic molecules will suppress destructive interference and thus favor the dark-state enhancement offered by heterodimers.https://doi.org/10.1088/1367-2630/ab25cadark state protectionlight harvestingpolaron transformorganic solar cellquantum heat engine |
| spellingShingle | D M Rouse E M Gauger B W Lovett Optimal power generation using dark states in dimers strongly coupled to their environment New Journal of Physics dark state protection light harvesting polaron transform organic solar cell quantum heat engine |
| title | Optimal power generation using dark states in dimers strongly coupled to their environment |
| title_full | Optimal power generation using dark states in dimers strongly coupled to their environment |
| title_fullStr | Optimal power generation using dark states in dimers strongly coupled to their environment |
| title_full_unstemmed | Optimal power generation using dark states in dimers strongly coupled to their environment |
| title_short | Optimal power generation using dark states in dimers strongly coupled to their environment |
| title_sort | optimal power generation using dark states in dimers strongly coupled to their environment |
| topic | dark state protection light harvesting polaron transform organic solar cell quantum heat engine |
| url | https://doi.org/10.1088/1367-2630/ab25ca |
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