Klein Michael, Gershuni Yonatan, Perutski Alisa, Hugonin Jean-Paul, Epstein Itai
School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 6997801, Israel.
Laboratoire Charles Fabry, Institut d'Optique Graduate School, Universite Paris-Saclay, CNRS, 91127 Palaiseau, France.
Nano Lett. 2025 Jun 4;25(22):8999-9005. doi: 10.1021/acs.nanolett.5c01352. Epub 2025 May 19.
Surface polaritons play a pivotal role in strong light-matter interactions at the nanoscale due to their ability to confine light to deep-subwavelength dimensions. A promising class of materials exhibiting such a polaritonic response is polar dielectrics, which support surface phonon polaritons (SPhPs). While SPhPs offer significantly lower losses compared to other polaritons, their potential has been underutilized due to their limited ability to reach large confinement factors. Here, we demonstrate a system composed of silver nanocubes deposited on a SiC polar dielectric, which experimentally realizes the antisymmetric-image-phonon-polariton mode, a hybridized SPhP mode that can confine mid-infrared radiation to extremely small mode volumes, almost a billion times smaller than their free-space volume, with quality factors an order-of-magnitude greater than those of surface plasmons or graphene plasmons, surpassing values of 180. Our method is general, scalable, and applicable to any polar dielectric, opening the path for controlling and manipulating strong light-matter interactions at the nanoscale in the long-wavelength range.
由于表面极化激元能够将光限制在深亚波长尺度，因此在纳米尺度的强光 - 物质相互作用中起着关键作用。一类展现出这种极化激元响应的很有前景的材料是极性电介质，其支持表面声子极化激元（SPhPs）。虽然与其他极化激元相比，SPhPs 的损耗显著更低，但由于它们达到大限制因子的能力有限，其潜力尚未得到充分利用。在此，我们展示了一个由沉积在 SiC 极性电介质上的银纳米立方体组成的系统，该系统通过实验实现了反对称镜像声子极化激元模式，这是一种杂化的 SPhP 模式，能够将中红外辐射限制在极小的模式体积内，几乎比其自由空间体积小十亿倍，品质因数比表面等离子体或石墨烯等离子体的品质因数大一个数量级以上，超过了 180 的值 我们的方法具有通用性、可扩展性，并且适用于任何极性电介质，为在长波长范围内纳米尺度上控制和操纵强光 - 物质相互作用开辟了道路。
