arXiv:1801.05220 · Physical Review A

General theory of Bose-Einstein condensation applied to an ideal quantum gas of photons in an optical microcavity

Eberhard E. Müller

Published Nov 18, 2019• 2 citations

Abstract

This paper provides, first, a succinct theoretical derivation of Bose-Einstein condensation in a grand-canonical ideal photon gas elaborating on previous results [M\"uller, Ann. Phys. 184, 219 (1988); Physica A (Amsterdam, Neth.) 139, 165 (1986)] additionally including new results on the condensate function and, second, applies this framework to consistently explain experimental findings on Bose-Einstein condensation of photons in an optical microcavity [Klaers, Schmitt, Vewinger, and Weitz, Nature 468, 545 (2010)]. A grand-canonical photon gas is realized by a steady state of a photon flux deviating from a canonical thermodynamic Planck equilibrium. The theoretical approach presented here invites to significantly widen the experimental framework for Bose-Einstein condensation of photons including three-dimensional photon resonators and thermalization mechanisms different from a dye medium in the cavity.

DOI: 10.1103/physreva.100.053837

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