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arXiv · 2511.03590

Spontaneous symmetry breaking in nonlinear superradiance

Nikolai D. Klimkin·Misha Ivanov
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Abstract

Creation and manipulation of non-classical states of light is rapidly becoming the focus of modern attosecond science. Here, we demonstrate numerically how interaction with such states can trigger the emergence of a many-body system with spontaneously broken symmetry by considering a modification of the well-known problem of superradiance encountered already by Dicke. Similarly to him, we investigate photon emission by ensembles of indistinguishable atoms. In contrast to him, however, we leverage symmetry-based selection rules to suppress emission of single photons by single atoms. A steady state is therefore only reached following a spontaneous transition into a collective symmetry-broken state of atoms and photonic modes. This transition permanently locks the atomic dipoles to the quantum field experienced by the system at a particular instant, transforming the entire setup into a potent quantum sensor reproducing the phase of the recorded quantum fluctuation.

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Nikolai D. Klimkin, Misha Ivanov. 2025-11-05. Spontaneous symmetry breaking in nonlinear superradiance. https://arxiv.org/abs/2511.03590

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