Crossover from exciton-polariton to photon Bose-Einstein condensation

Abstract

BEC of exciton-polaritons and related effects such as superfluidity1,2, spontaneous symmetry breaking3,4 and quantised vortices5,6 open way to creation of novel light sources7 and optical logic elements8. Remarkable observations of exciton-polariton BEC in microcavities9-12 have been reported in the recent ten years. Very recently, thermalisation and subsequent condensation of cavity photons in a dye-filled microcavity have been observed13. Here we show that BEC of both exciton-polaritons and photons can be created in the same system under different optical excitation conditions. A dynamic phase transition between a photon and a polariton BEC takes place after a single high-power excitation pulse and we find both condensed states in thermal equilibrium with the excited states. At the crossover, photons and polaritons coexist, which results in a decrease in the long-range spatial coherence. Build-up and successive depinning of polarisation is observed at the threshold of both polariton and photon condensation.

References in corpus (10)

• Observation of Superfluidity of Polaritons in Semiconductor Microcavities
• Quantised Vortices in an Exciton-Polariton Fluid
• Bose-Einstein condensation of photons in an optical microcavity
• Quantum-fluid dynamics of microcavity polaritons
• Spontaneous Polarisation Build up in a Room Temperature Polariton Laser
• Thermalisation of a two-dimensional photonic gas in a 'white-wall' photon box
• Photon lasing in a GaAs microcavity: similarities with a polariton condensate
• Spontaneous symmetry breaking in a polariton and photon laser
• Dynamics of formation and decay of coherence in a polariton condensate
• Polariton Condensation and Lasing