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arXiv:2602.00633

Near-losslesss method for generating thermal photon-bunched light

Xi Jie Yeo, Darren Ming Zhi Koh, Justin Yu Xiang Peh, Christian Kurtsiefer, Peng Kian Tan

quant-phSubmitted Jan 31, 2026• Announced Feb 3, 2026• 0 citations
v1 · Jan 31, 2026v2 · Feb 5, 2026
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Abstract

Thermal light sources exhibiting photon bunching have been suggested for sensing applications that exploit timing correlations of stationary light, including range finding, clock synchronization, and non-line-of-sight imaging. However, these proposals have remained unrealized in practice because available sources of photon bunching either possess coherence times too short to be timing resolved by photodetectors, or produce brightness levels too low to tolerate realistic return losses. In this work, we demonstrate a low-loss method for generating photon bunching with a conversion efficiency nearly 9 orders of magnitude higher than that achieved by many other bunching processes.

Comments
5 pages, 6 figures

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Thermal light sources exhibiting photon bunching have been suggested for sensing applications that exploit timing correlations of stationary light, including range finding, clock synchronization, and non-line-of-sight imaging. However, these proposals have remained unrealized in practice because available sources of photon bunching either possess coherence times too short to be timing resolved by photodetectors, or produce brightness levels too low to tolerate realistic return losses. In this work, we demonstrate a low-loss method for generating photon bunching with a conversion efficiency nearly 9 orders of magnitude higher than that achieved by many other bunching processes.
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Temporal photon bunching is the phenomena in which photons tend to cluster together on a short time scale. This effect can be quantified using the second order coherenceg(2)(τ)g^{(2)}(\tau)g(2)(τ)of the light. Photon bunching has been utilized in LIDAR, ghost imaging and simulating star light. In these applications, bunched light is typically generated inefficiently by sending coherent laser light through a phase randomization media, such as a rotating ground glass [1] or a liquid suspension of microspheres [2].
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