Fourier-plane microscopy is a powerful tool for measuring the angular optical response of a plethora of materials and photonic devices. Among them, optical microcavities feature distinctive energy-momentum dispersions, crucial for a broad range of fundamental studies and applications. However, measuring the whole momentum space (k-space) with sufficient spectral resolution using standard spectroscopic techniques is challenging, requiring long and alignment-sensitive scans. Here, we introduce a k-space hyperspectral microscope, which uses a common-path birefringent interferometer to image photoluminescent organic microcavities, obtaining an angle- and wavelength-resolved view of the samples in only one measurement. The exceptional combination of angular and spectral resolution of our technique allows us to reconstruct a three-dimensional (3D) map of the cavity dispersion in the energy-momentum space, revealing the polarization-dependent behavior of the resonant cavity modes. Furthermore, we apply our technique for the characterization of a dielectric nanodisk metasurface, evidencing the angular and spectral behavior of its anapole mode. This approach is able to provide a complete optical characterization for materials and devices with nontrivial angle-/wavelength-dependent properties, fundamental for future developments in the fields of topological photonics and optical metamaterials.

中文翻译：

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双折射共光路干涉仪的 k 空间高光谱成像


傅立叶平面显微镜是测量多种材料和光子器件的角光学响应的​​强大工具。其中，光学微腔具有独特的能量动量色散，对于广泛的基础研究和应用至关重要。然而，使用标准光谱技术以足够的光谱分辨率测量整个动量空间（ k空间）具有挑战性，需要长时间且对准敏感的扫描。在这里，我们介绍了一种k空间高光谱显微镜，它使用共光路双折射干涉仪对光致发光有机微腔进行成像，只需一次测量即可获得样品的角度和波长分辨视图。我们的技术将角度分辨率和光谱分辨率完美结合，使我们能够重建能量动量空间中腔体色散的三维 (3D) 图，揭示谐振腔模式的偏振相关行为。此外，我们应用我们的技术来表征介电纳米盘超表面，证明其折极模式的角度和光谱行为。这种方法能够为具有重要角度/波长相关特性的材料和器件提供完整的光学表征，这对于拓扑光子学和光学超材料领域的未来发展至关重要。