AI 中文总结
研究通过建立时空傅里叶对应关系，利用时间傅里叶光学框架及TPSF重建方法，从实验光谱中恢复隐藏信息，揭示混合光-物质态和强耦合，为相关测量开辟新机会。
AI 中文摘要
光谱测量通过揭示共振、模式杂交和光-物质相互作用，为波系统提供了基本见解。然而，固有耗散和测量引起的光谱展宽常常掩盖了产生测量光谱的潜在混合光-物质态。在此，我们建立了一种时空傅里叶对应关系，将光谱展宽解释为有效的时间衰减，从而产生了一个用于恢复隐藏光谱信息的时间傅里叶光学框架。该框架通过时间点扩展函数（TPSF）重建方法实现，在傅里叶变换之前补偿有效的时间衰减，直接从实验测量的光谱中重建固有光谱响应，而无需重复频率合成或依赖模型的拟合。我们在确定性单分子金纳米球二聚体以及与J聚集体激子耦合的基于金@银纳米棒和纳米三角形的开放等离子体纳米腔中对该方法进行了实验验证。在这些不同的平台上，TPSF始终能够重建隐藏的上下极化分支，从而揭示传统散射光谱中未解决的潜在混合光-物质态和强耦合。重建的光谱与最近开发的复频形式主义密切吻合，同时提供了一种相当简单且更易于实验实现的方法。除了强光-物质耦合之外，时间傅里叶光学还建立了一个用于揭示被耗散隐藏的物理状态的通用框架，为光子学和波物理学中的光谱学、成像、传感和逆波测量开辟了新机会。
英文摘要
Spectral measurements provide fundamental insights into wave systems by revealing resonances, mode hybridization, and light-matter interactions. However, intrinsic dissipation and measurement-related spectral broadening often obscure the spectral signatures of the underlying hybridized light-matter states. Here, we establish a temporal Fourier optics framework based on a space-time Fourier correspondence, which interprets spectral broadening as the Fourier counterpart of temporal attenuation. This perspective introduces a temporal point-spread function (TPSF) that enables direct, synthesis-free reconstruction of the underlying spectral response from experimentally measured spectra by compensating for effective temporal decay before transformation back to the frequency domain. We experimentally validate the framework using deterministic single-molecule Au nanosphere dimers and open Au@Ag nanorod- and nanotriangle-based plasmonic nanocavities coupled to J-aggregate excitons. Across these distinct platforms, TPSF consistently resolves hidden upper and lower polaritonic branches, revealing hybridized light-matter states and strong coupling that remain inaccessible in conventional scattering spectra. The reconstructed spectra agree closely with the recently developed complex-frequency formalism while providing a substantially simpler and experimentally accessible implementation. More broadly, temporal Fourier optics establishes a general framework for recovering dissipation-obscured spectral information, opening new opportunities for spectroscopy, imaging, sensing, and inverse wave measurements across photonics and wave physics.
Comments27 pages, 4 figures
