Quantum-enhanced capture of photons using optical ratchet states
Abstract
Natural and artificial light harvesting systems often operate in a regime where the flux of photons is relatively low. Besides absorbing as many photons as possible it is therefore paramount to prevent excitons from annihilation via photon re-emission until they have undergone an irreversible energy conversion process. Taking inspiration from photosynthetic antenna structures, we here consider ring-like systems and introduce a class of states we call ratchets: excited states capable of absorbing but not emitting light. This allows our antennae to absorb further photons whilst retaining the excitations from those that have already been captured. Simulations for a ring of four sites reveal a peak power enhancement by up to a factor of 35 under ambient conditions owing to a combination of ratcheting and the prevention of emission through dark-state population. In the slow extraction limit the achievable power enhancement due to ratcheting alone exceeds 20%.
Keywords
Cite
@article{arxiv.1504.05849,
title = {Quantum-enhanced capture of photons using optical ratchet states},
author = {K. D. B. Higgins and B. W. Lovett and E. M. Gauger},
journal= {arXiv preprint arXiv:1504.05849},
year = {2017}
}
Comments
major revision with improved model (all data and figures updated)