Polariton condensation in photonic crystals with high molecular orientation

We study Frenkel exciton-polariton Bose–Einstein condensation in a two-dimensional defect-free triangular photonic crystalwith an organic semiconductor activemediumcontaining bound excitons with dipolemoments oriented perpendicular to the layers.We find photonic Blochmodes of the structure and consider their strong coupling regimewith the excitonic component.Using theGross– Pitaevskii equation for exciton polaritons and the Boltzmann equation for the external exciton reservoir, we demonstrate the formation of condensate at the points in reciprocal spacewhere photon group velocity equals zero. Further,we demonstrate condensation at non-zeromomentumstates for transverse magnetic-polarized photons in the case of a systemwith incoherent pumping, and showthat the condensation threshold varies for different points in the reciprocal space, controlled by detuning. © 2018 The Author(s). Published by IOP Publishing Ltd on behalf of Deutsche Physikalische Gesellschaft101sciescopu