Interplay of coherent and dissipative dynamics in condensates of light

Abstract

Based on the Lindblad master equation approach we obtain a detailed microscopic model of photons in a dye-filled cavity, which features condensation of light. To this end we generalise a recent nonequilibrium approach of Kirton and Keeling such that the dye-mediated contribution to the photonphoton interaction in the light condensate is accessible due to an interplay of coherent and dissipative dynamics. We describe the steady-state properties of the system by analysing the resulting equations of motion of both photonic and matter degrees of freedom. In particular, we discuss the existence of two limiting cases for steady states: photon Bose-Einstein condensate and laser-like. In the former case, we determine the corresponding dimensionless photon-photon interaction strength by relying on realistic experimental data and find a good agreement with previous theoretical estimates. Furthermore, we investigate how the dimensionless interaction strength depends on the respective system parameters.

Cloud shape of a molecular Bose–Einstein condensate in a disordered trap: a case study of the dirty boson problem

“…First, we are going to use the cumulant expansion method [75][76][77], where in the Gaussian approximation all the cumulants of higher than second order are neglected. The general expansion method and the approximation procedure are outlined in appendix A.…”

Anisotropic Superfluidity in a Weakly Interacting Condensate of Quasi‐2D Photons

“…For a dye-photon cavity, the interactions are governed by the thermo-optical effects [2,11] and, additionally, the χ (3) Kerr-type non-linearity. [12] Theoretical calculations from the correlation data [13] and the master-equation model [14] provide rather low estimates for the dimensionless 2D interaction parameter [15]g ≈ 10 −7 − 10 −4 . Experimentally, the thermo-optic part of interaction proves to be dominant, with g ≈ 10 −4 , [2,16] while the Kerr non-linearity may arguably be enhanced by adding suitable materials to the dye solution.…”

“…Comparing the expression for the condensate contribution to the energy (23) with (14) and noticing that (q · P) 2 = q 2…”

Cooperative phases and phase transitions of Bose condensed light in dye filled cavities

“…Creation of BEC of light [10][11][12][13][14], has opened up a new chapter in the search for strongly interacting phases of light. In these experiments the thermalization of light is achieved through absorption and reemission of photons by dye molecules which represent a thermal bath-thanks to their manifolds of rovibrational states exchanging energy with the solvent [15,16]. The equilibration of light occurs on much faster scale than the photon escape from the cavity.…”

“…It can be induced by external fields (see appendix B) or form spontaneously as a part of the orientational disorder (on a time scale shorter than τ r ). Then, the tensor d ij in equation (10) will deviate from the isotropic form(16) so that its eigenvalues , m m become unequal to each other. Without loss of generality we will assume that 0…”