Galiffi Emanuele, Solís Diego Martínez, Yin Shixiong, Engheta Nader, Alù Andrea
Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, 10031, USA.
Departamento de Tecnología de los Computadores y de las Comunicaciones, University of Extremadura, 10003, Cáceres, Spain.
Light Sci Appl. 2025 Sep 23;14(1):338. doi: 10.1038/s41377-025-01947-2.
Exotic forms of wave control have been emerging by engineering matter in space and time. In this framework, temporal photonic interfaces, i.e., abrupt changes in the electromagnetic properties of a material, have been shown to induce temporal scattering phenomena dual to spatial reflection and refraction, at the basis of photonic time crystals and space-time metamaterials. Despite decades-old theoretical studies on these topics, and recent experimental demonstrations, the careful modeling of these phenomena has been lagging behind. Here, we develop from first principles a rigorous model of the electrodynamics of temporal photonic interfaces, highlighting the crucial role of the mechanisms driving time variations. We demonstrate that the boundary conditions and conservation laws associated with temporal scattering may substantially deviate from those commonly employed in the literature, based on their microscopic implementation. Our results open new vistas for both fundamental investigations over light-matter interactions in time-varying structures and for the prospect of their future implementations and applications in optics and photonics.
通过在空间和时间上对物质进行工程设计，各种奇特的波控制形式不断涌现。在此框架下，时间光子界面，即材料电磁特性的突然变化，已被证明能引发与空间反射和折射对偶的时间散射现象，这是光子时间晶体和时空超材料的基础。尽管对这些主题已有数十年的理论研究以及近期的实验验证，但对这些现象的精确建模仍滞后。在此，我们从第一原理出发，开发了一种时间光子界面电动力学的严格模型，突出了驱动时间变化机制的关键作用。我们证明，基于微观实现，与时间散射相关的边界条件和守恒定律可能与文献中常用的有很大偏差。我们的结果为研究时变结构中光与物质相互作用的基础研究以及它们未来在光学和光子学中的实现与应用前景开辟了新视野。
