Polaritons are quasiparticles formed by entanglement of a photon with an excitation of a molecule or atom. Recent experimental work on inorganic microcavities has shown that these quasiparticles can undergo a phase transition to form a Bose–Einstein condensate with a transition temperature approaching room temperature. This Demonstration computes the polariton dispersion curve for a layer of anthracene sandwiched between two reflecting mirrors. The cavity gap, , determines the cutoff frequency for a photon in the cavity and is the photon wavevector parallel to the mirrors. Computed are the effective mass of a lower polariton and the nonlinearity parameter for the Gross–Pitaevskii equation describing a polariton condensate state.
This Demonstration is based upon work sponsored by the National Science Foundation (CHE-1011894).
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