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arXiv · 2503.16695

Stabilizing open photon condensates by ghost-attractor dynamics

Aya Abouelela·Michael Turaev·Roman Kramer·Moritz Janning·Michael Kajan·Sayak Ray·Johann Kroha
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Abstract

We study the temporal, driven-dissipative dynamics of open photon Bose-Einstein condensates (BEC) in a dye-filled microcavity, taking the condensate amplitude and the noncondensed fluctuations into account on the same footing by means of a cumulant expansion within the Lindblad formalism. The fluctuations fundamentally alter the dynamics in that the BEC always dephases to zero for sufficiently long time. However, a ghost-attractor, although it is outside of the physically accessible configuration space, attracts the dynamics and leads to a plateau-like stabilization of the BEC for an exponentially long time, consistent with experiments. We also show that the photon BEC and the lasing state are separated by a true phase transition, since they are characterized by different fixed points. The ghost-attractor nonequilibrium stabilization mechanism is alternative to prethermalization and may possibly be realized on other dynamical platforms as well.

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Aya Abouelela, Michael Turaev, Roman Kramer, Moritz Janning, Michael Kajan, Sayak Ray, Johann Kroha. 2025-07-09. Stabilizing open photon condensates by ghost-attractor dynamics. https://doi.org/10.1103/hcsq-dwcg

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