Polaritons in Semiconducting Organic Films

dispersion

data table

L (Å)

2500

E

b

(eV)

0.012

dielectric const

2.99

Rabi freq (eV)

0.15

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,

L

, determines the cutoff frequency for a photon in the cavity and

k

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.