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arXiv · 2607.17647

Active Optical Frequency Measurements with Superradiance Prolonged by a Modulated Magnetic Field

Huihui Yu·Shi-Lei Su·Chongxin Shan·Klaus Mølmer·Yuan Zhang
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Abstract

Superradiant emission from long-lived excited states of an atomic ensemble confined in an optical cavity constitutes a practical source of light with narrow linewidth. In the pulsed regime, however, superradiance implies rapid emission and a broadening of the spectrum. Recent experiments have demonstrated constructive and destructive interference of superradiant emission by different strontium atomic transitions. In this article, we show that by modulating the atomic transition frequencies with a magnetic field, it is possible to control the release of the atomic excitation energy as a prolonged pulse or a train of superradiant pulses. By simulations, we show that heterodyne detection of the prolonged superradiance shows extremely sharp spectral features, which leads to significantly reduced frequency uncertainty and fluctuation.

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Huihui Yu, Shi-Lei Su, Chongxin Shan, Klaus Mølmer, Yuan Zhang. 2026-07-20. Active Optical Frequency Measurements with Superradiance Prolonged by a Modulated Magnetic Field. https://arxiv.org/abs/2607.17647

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