Effective interaction and condensation of dipolaritons in coupled   quantum wells
  Dipolaritons are a three-way superposition of photon, a direct exciton, and an indirect exciton that are formed in coupled quantum well microcavities. As is the case with exciton-polaritons, dipolaritons have a self-interaction due to direct and exchange effects of the underlying electrons and holes. Here we present a theoretical description of dipolaritons and derive simple formulas for their basic parameters. In particular, we derive the effective dipolariton-dipolariton interaction taking into account of exchange effects between the excitons. We obtain a simple relation to describe the effective interaction at low densities. We find that dipolaritons should condense under suitable conditions, described by a dissipative Gross-Pitaevskii equation. While the parameters for condensation are promising, we find that the level of tunability of the interactions is limited. 
Tim Byrnes, German V. Kolmakov, Roman Ya. Kezerashvili, Yoshihisa   Yamamoto
cond-mat.quant-gas cond-mat.mes-hall