Coherence measurements of polaritons in thermal equilibrium reveal a power law for two-dimensional condensates

Abstract

We have created a spatially homogeneous polariton condensate in thermal equilibrium, up to very high condensate fraction. Under these conditions, we have measured the coherence as a function of momentum, and determined the total coherent fraction of this boson system from very low density up to density well above the condensation transition. These measurements reveal a consistent power law for the coherent fraction as a function of the total density over nearly three orders of its magnitude. The same power law is seen in numerical simulations solving the two-dimensional Gross-Pitaevskii equation for the equilibrium coherence. This power law has not been predicted by prior analytical theories.

References in corpus (3)

• Emergence of coherence in a uniform quasi-two-dimensional Bose gas
• Quantum Gases in Optical Boxes
• Slow reflection and two-photon generation of microcavity exciton-polaritons

Cited by in corpus (5)

• Bose-Einstein condensation of polaritons at room temperature in a GaAs/AlGaAs structure
• Narrow-linewidth exciton-polariton laser
• Persistent, controllable circulation of a polariton ring condensate
• Quantum coherence of a long-lifetime exciton-polariton condensate
• Strong coupling of polaritons at room temperature in a GaAs/AlGaAs structure