近日，香港城市大学的区泽宇及其研究小组与天津大学的李小英等人合作并取得一项新进展。经过不懈努力，他们揭示了用于完整测量复相干函数的相位依赖型汉伯里-布朗和特威斯效应。相关研究成果已于2025年1月13日在国际知名学术期刊《光：科学与应用》上发表。

该研究团队通过在强度相关测量之前，将强度匹配的参考场与输入场进行混合，来扩展汉伯里-布朗和特威斯（HBT）干涉仪。当以易于获取的相干态作为参考场时，研究人员实验上演示了当输入场为连续波或非稳态脉冲波的热场时，所表现出的对相位敏感的双光子干涉效应，并且无需将输入场从不同位置合并，即可测量其完整的复二阶相干函数。

此外，研究人员讨论了如何使用更现实的连续波宽带反聚束光场，作为参考场来提高信号水平。这项研究为开发遥感和干涉成像新技术奠定了基础，这些技术在长基线高分辨率天文学等领域具有应用价值。

据悉，汉伯里-布朗和特威斯（HBT）效应是恒星强度干涉测量的基础。然而，它是一种对相位不敏感的双光子干涉效应。

附：英文原文

Title: Phase-dependent Hanbury-Brown and Twiss effect for the complete measurement of the complex coherence function

Author: Tang, Xuan, Zhang, Yunxiao, Guo, Xueshi, Cui, Liang, Li, Xiaoying, Ou, Z. Y.

Issue&Volume: 2025-01-13

Abstract: Hanbury-Brown and Twiss (HBT) effect is the foundation for stellar intensity interferometry. However, it is a phase insensitive two-photon interference effect. Here we extend the HBT interferometer by mixing intensity-matched reference fields with the input fields before intensity correlation measurement. With the freely available coherent state serving as the reference field, we experimentally demonstrate the phase sensitive two-photon interference effect when the input fields are thermal fields in either continuous wave or non-stationary pulsed wave and measure the complete complex second-order coherence function of the input fields without bringing them together from separate locations. Moreover, we discuss how to improve the signal level by using the more realistic continuous wave broadband anti-bunched light fields as the reference field. Our investigations pave the way for developing new technology of remote sensing and interferometric imaging with applications in long baseline high-resolution astronomy.

DOI: 10.1038/s41377-024-01684-y

Source: https://www.nature.com/articles/s41377-024-01684-y