Light Harvesting Enhanced by Quantum Ratchet States

Abstract

We consider bioinspired ring systems as photovoltaic circuits to explore the advantage of “optical ratcheting,” a process whereby the arrangement of coupled optical dipoles enables delocalized excitonic states that are protected against radiative decay whilst permitting the absorption of further photons. We explore how the performance of a ratcheting antenna scales with system size when excitons are incoherently or coherently extracted from the antenna to an associated trap site. In both instances we also move to the polaron frame in order to more closely model realistic systems where the coupling to vibrational modes can generally be assumed to be strong. We find a multifaceted and nuanced dependence of the predicted performance on an interplay between geometrical arrangement, extraction mechanism, and vibrational coupling strength. Certain regimes support substantial performance improvements in the power extracted per site.8 MoreReceived 14 September 2022Revised 21 December 2022Accepted 18 January 2023DOI:https://doi.org/10.1103/PRXEnergy.2.013002Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.Published by the American Physical SocietyPhysics Subject Headings (PhySH)Research AreasOpen quantum systemsSolar energy harvesting devicesPhysical SystemsRing polymersPropertiesElectric momentTechniquesDensity matrix methodsEnergy Science & TechnologyAtomic, Molecular & OpticalCondensed Matter, Materials & Applied Physics