Polariton condensation in photonic molecules.

We report on polariton condensation in photonic molecules formed by two coupled micropillars. We show that the condensation process is strongly affected by the interaction with the cloud of uncondensed excitons and thus strongly depends on the exact localization of these excitons within the molecule. Under symmetric excitation conditions, condensation is triggered on both binding and antibinding polariton states of the molecule. On the opposite, when the excitonic cloud is injected in one of the two pillars, condensation on a metastable state is observed and a total transfer of the condensate into one of the micropillars can be achieved. Our results highlight the crucial role played by relaxation kinetics in the condensation process.