Nonequilibrium photon condensates

Michiel Wouters

UAntwerpen -

We present a classical field model to describe lattices of photon condensates that are thermalized by their interaction with a bath of dye molecules. The thermalization of the system is captured by a frequency-dependent loss term. Together with the fluctuations due to spontaneous emission, this model describes thermalisation dynamics an ideal bose gas by repeated emission and absorption by molecules. The driving and dissipation because of cavity losses enriches the physics of photon condensates. We discuss the coherence in lattices of photon condensates as well as the formation of quantized vortices and describe the Berezinskii-Kosterlitz-Thouless phase transition where vortex-antivortex pairs are formed by thermal fluctuations. We highlight the role of driving and dissipation in all these phenomena.

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