近日，德国马克斯·普朗克多学科科学研究所Claus Ropers团队报道了电子预示着非经典光。该研究于2025年10月16日发表在《自然—物理学》杂志上。

自由电子是电磁场的普遍存在，从根本上说，其量子化能量交换可能有助于产生可调谐的量子光。由于发射辐射的量子特征是在联合电子和光子状态下编码的，因此它们只能通过访问两个子系统的测量来揭示。

研究组证明了由自由电子产生这种非经典光态的相干参数。通过研究电子-光子的相关性，研究组发现量子化的电子能量损失预示着介电波导中产生的光子数量。在Hanbury Brown-Twiss测量中，研究组观察到电子预示的单光子状态与反聚束强度相关，而单个电子的双量子能量损失产生明显的双光子巧合。该研究结果将使在与自由电子束控制相互作用的基础上，定制更高数量的Fock和其他光学量子态的制备成为可能。

附：英文原文

Title: Electrons herald non-classical light

Author: Arend, Germaine, Huang, Guanhao, Feist, Armin, Yang, Yujia, Henke, Jan-Wilke, Qiu, Zheru, Jeng, Hao, Raja, Arslan Sajid, Haindl, Rudolf, Wang, Rui Ning, Kippenberg, Tobias J., Ropers, Claus

Issue&Volume: 2025-10-16

Abstract: Free electrons are a universal source of electromagnetic fields, and fundamentally their quantized energy exchange may facilitate generating tunable quantum light. Because the quantum features of the emitted radiation are encoded in the joint electronic and photonic state, they can only be revealed by a measurement accessing both subsystems. Here we demonstrate the coherent parametric generation of such non-classical states of light by free electrons. Investigating electron–photon correlations, we show that the quantized electron energy loss heralds the number of photons generated in a dielectric waveguide. In Hanbury Brown–Twiss measurements, we observe an electron-heralded single-photon state using antibunching intensity correlation, whereas two-quantum energy losses of individual electrons yield pronounced two-photon coincidences. Our results will enable the tailored preparation of higher-number Fock and other optical quantum states on the basis of controlled interactions with free-electron beams.

DOI: 10.1038/s41567-025-03033-1

Source: https://www.nature.com/articles/s41567-025-03033-1