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arXiv · 2511.10556

Observation and Manipulation of Optical Parametric Down-Conversion in the Langevin Regime

Yen-Ju Chen·Chun-Yuan Cheng·Tien-Dat Pham·Tzu-An Chen·Chang-Hau Kuo·Yen-Hung Chen·Chih-Sung Chuu
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Abstract

Quantum fluctuation plays a key role in the parametric down-conversion in the Langevin regime. In this paper, we report the experimental realization of optical parametric down-conversion in the Langevin regime on a chip. By precisely controlling the loss inherently tied to fluctuation, we observe the asymmetric Hong-Ou-Mandel dip - a hallmark of quantum fluctuation in the fluctuation-driven PDC, and the fluctuation-induced compression of single photons by nearly one order of magnitude. These findings pave the way for the manipulation of quantum fluctuation, quantum states, and system-reservoir interaction.

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Yen-Ju Chen, Chun-Yuan Cheng, Tien-Dat Pham, Tzu-An Chen, Chang-Hau Kuo, Yen-Hung Chen, Chih-Sung Chuu. 2025-11-13. Observation and Manipulation of Optical Parametric Down-Conversion in the Langevin Regime. https://doi.org/10.1103/mcxn-x7bz

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