近日，美国麻省理工学院Comin, Riccardo团队研究了基于二维磁体的可调谐纳米光子器件和腔。该项研究成果发表在2025年7月8日出版的《自然—光子学》上。
纳米光子学领域的核心是设计光通过纳米级结构的能力。这些结构通常具有永久的工作光谱范围和在制造过程中固定的光学特性。量子材料具有相互关联和交织的自由度，为动态控制光子器件而不改变其物理结构提供了一条有前途的途径。
研究组用范德华反铁磁半导体CrSBr制作光子晶体板，并演示了对其光学特性的原位控制。利用CrSBr在激子共振附近的超大折射率及其通过外场的可调性，他们实现了近可见光和红外波长光子模式的精确操纵，展示了纳米光子器件设计的新范例。由此产生的光子晶体的引导共振在光谱中紧密堆积，模式体积非常小，可以通过外部磁场高度调谐，并且Q因子超过1200。这些共振自杂化与激子自由度，导致本征强光-物质耦合。该发现强调了量子材料在发展原位可调谐光子元件和腔方面的潜力。
附：英文原文
Title: Tunable nanophotonic devices and cavities based on a two-dimensional magnet
Author: Demir, Ahmet Kemal, Nessi, Luca, Vaidya, Sachin, Occhialini, Connor A., Soljai, Marin, Comin, Riccardo
Issue&Volume: 2025-07-08
Abstract: Central to the field of nanophotonics is the ability to engineer the flow of light through nanoscale structures. These structures often have permanent working spectral ranges and optical properties that are fixed during fabrication. Quantum materials, with their correlated and intertwined degrees of freedom, offer a promising avenue for dynamically controlling photonic devices without altering their physical structure. Here we fabricate photonic crystal slabs from CrSBr, a van der Waals antiferromagnetic semiconductor, and demonstrate in situ control over their optical properties. Leveraging the combination of the exceptionally large refractive index of CrSBr near its excitonic resonances and its tunability via external fields, we achieve precise manipulation of photonic modes at near-visible and infrared wavelengths, showcasing a new paradigm for nanophotonic device design. The resulting guided resonances of the photonic crystal are tightly packed in the spectrum with very small mode volumes, are highly tunable via external magnetic fields and exhibit high Q factors exceeding 1,200. These resonances self-hybridize with the excitonic degrees of freedom, resulting in intrinsic strong light–matter coupling. Our findings underscore the potential of quantum materials for developing in situ tunable photonic elements and cavities.
DOI: 10.1038/s41566-025-01712-2
Source: https://www.nature.com/articles/s41566-025-01712-2