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arXiv · 2504.11018

Cavity cooling using ultrafast electrons

D. E. Maison·L. Stettiner·S. Even-Haim·A. Gorlach·I. Kaminer
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Abstract

We propose a method to cool a thermal photonic state in a cavity by passing electrons through it. Electrons are coherently split into two paths, with one path traversing the cavity, becoming entangled with its photonic state. A sequence of such entanglement interactions can achieve cooling of the cavity: e.g., a twofold reduction in thermal photon number with a 25% post-selection probability. This ``which-path''-based approach extends to other qubit oscillator systems, such as phonons in crystals or optomechanical resonators, offering a general framework for quantum oscillator cooling.

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D. E. Maison, L. Stettiner, S. Even-Haim, A. Gorlach, I. Kaminer. 2025-04-15. Cavity cooling using ultrafast electrons. https://doi.org/10.1103/fnhk-lknl

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