Optical Properties of Single Infrared Resonant Circular Microcavities for Surface Phonon Polaritons

作者：Tao Wang, Peining Li, Benedikt Hauer, Dmitry N. Chigrin, Thomas Taubner · 发表于：Nano Letters · 年份：2013 · DOI：10.1021/nl4020342 · 被引用次数：128 · 研究领域：Plasmonic and Surface Plasmon Research、Thermal Radiation and Cooling Technologies、Metamaterials and Metasurfaces Applications

Plasmonic antennas are crucial components for nano-optics and have been extensively used to enhance sensing, spectroscopy, light emission, photodetection, and others. Recently, there is a trend to search for new plasmonic materials with low intrinsic loss at new plasmon frequencies. As an alternative to metals, polar crystals have a negative real part of permittivity in the Reststrahlen band and support surface phonon polaritons (SPhPs) with weak damping. Here, we experimentally demonstrate the resonance of single circular microcavities in a thin gold film deposited on a silicon carbide (SiC) substrate in the mid-infrared range. Specifically, the negative permittivity of SiC leads to a well-defined, size-tunable SPhP resonance with a Q factor of around 60 which is much higher than those in surface plasmon polariton (SPP) resonators with similar structures. These infrared resonant microcavities provide new possibilities for widespread applications such as enhanced spectroscopy, sensing, coherent thermal emission, and infrared photodetectors among others throughout the infrared frequency range.