Auad Yves, Dias Eduardo J C, Tencé Marcel, Blazit Jean-Denis, Li Xiaoyan, Zagonel Luiz Fernando, Stéphan Odile, Tizei Luiz H G, García de Abajo F Javier, Kociak Mathieu
Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405, Orsay, France.
ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860, Castelldefels, Barcelona, Spain.
Nat Commun. 2023 Jul 24;14(1):4442. doi: 10.1038/s41467-023-39979-0.
The synergy between free electrons and light has recently been leveraged to reach an impressive degree of simultaneous spatial and spectral resolution, enabling applications in microscopy and quantum optics. However, the required combination of electron optics and light injection into the spectrally narrow modes of arbitrary specimens remains a challenge. Here, we demonstrate microelectronvolt spectral resolution with a sub-nanometer probe of photonic modes with quality factors as high as 10. We rely on mode matching of a tightly focused laser beam to whispering gallery modes to achieve a 10-fold increase in light-electron coupling efficiency. By adapting the shape and size of free-space optical beams to address specific physical questions, our approach allows us to interrogate any type of photonic structure with unprecedented spectral and spatial detail.
自由电子与光之间的协同作用最近已被利用，以达到令人印象深刻的空间和光谱分辨率，从而实现了在显微镜和量子光学中的应用。然而，将电子光学与光注入到任意样品的光谱窄模式所需的组合仍然是一个挑战。在这里，我们展示了具有高达10的品质因数的光子模式的亚纳米探针的微电子伏特光谱分辨率。我们依靠将紧密聚焦的激光束与回音壁模式进行模式匹配，以实现光电子耦合效率提高10倍。通过调整自由空间光束的形状和大小来解决特定的物理问题，我们的方法使我们能够以前所未有的光谱和空间细节来探测任何类型的光子结构。
