  In this work, we propose an efficient photocell based on GaN quantum dots. We
exploit the strong built-in electric field in GaN QDs and excitonic
dipole-dipole coupling between adjacent QDs to break detailed balance. This is
a much stronger effect than Fano interference, and we show that such a
photocell exhibits enhanced photo-voltage and photocurrent over its
conventional counterpart. The proposed quantum photocell could be the first
step towards harnessing quantum effects in practical energy harvesting devices.
