Menabde Sergey G, Heiden Jacob T, Cox Joel D, Mortensen N Asger, Jang Min Seok
School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
Center for Nano Optics, University of Southern Denmark, DK-5230 Odense, Denmark.
Nanophotonics. 2022 Jan 4;11(11):2433-2452. doi: 10.1515/nanoph-2021-0693. eCollection 2022 Jun.
Polaritonic modes in low-dimensional materials enable strong light-matter interactions and the manipulation of light on nanometer length scales. Very recently, a new class of polaritons has attracted considerable interest in nanophotonics: image polaritons in van der Waals crystals, manifesting when a polaritonic material is in close proximity to a highly conductive metal, so that the polaritonic mode couples with its mirror image. Image modes constitute an appealing nanophotonic platform, providing an unparalleled degree of optical field compression into nanometric volumes while exhibiting lower normalized propagation loss compared to conventional polariton modes in van der Waals crystals on nonmetallic substrates. Moreover, the ultra-compressed image modes provide access to the nonlocal regime of light-matter interaction. In this review, we systematically overview the young, yet rapidly growing, field of image polaritons. More specifically, we discuss the dispersion properties of image modes, showcase the diversity of the available polaritons in various van der Waals materials, and highlight experimental breakthroughs owing to the unique properties of image polaritons.
低维材料中的极化激元模式能够实现强光与物质的相互作用，并在纳米尺度上对光进行操控。最近，一类新型极化激元在纳米光子学领域引起了广泛关注：范德华晶体中的镜像极化激元，当极化激元材料靠近高导电性金属时会出现，此时极化激元模式与其镜像发生耦合。镜像模式构成了一个引人注目的纳米光子平台，它能将光场压缩到纳米体积中，达到无与伦比的程度，同时与在非金属衬底上的范德华晶体中的传统极化激元模式相比，具有更低的归一化传播损耗。此外，超压缩镜像模式提供了进入光与物质相互作用非局域区域的途径。在这篇综述中，我们系统地概述了镜像极化激元这个新兴但发展迅速的领域。更具体地说，我们讨论了镜像模式的色散特性，展示了各种范德华材料中可用极化激元的多样性，并强调了由于镜像极化激元的独特性质而取得的实验突破。
