AI 中文总结
本文首次精确测量锑纳米薄膜在紫外至远红外的宽谱介电函数，发现巨带间跃迁主导响应，并展示可调谐等离激元和介电共振，为宽带纳米光子器件提供新路径。
AI 中文摘要
半金属元素锑（Sb）纳米结构在纳米光子学特性起关键作用的应用中展现出巨大潜力，例如相变光学存储器、非线性光学元件、光热治疗剂、光电探测器和光催化剂。然而，设计先进的基于锑的光子器件迫切需要准确可靠地了解块体和纳米尺度锑的光学响应。在此，我们首次报道了锑纳米薄膜在从紫外到远红外的宽光谱范围（4 - 0.04 eV，即约 0.3 - 30 微米）内完全一致且精确测量的介电函数，超越了先前探索有限光谱范围的报道。研究发现，锑的光谱响应完全由可见光到中红外（4 - 0.4 eV，即约 0.3 - 3 微米）的巨带间跃迁驱动，并且其贡献在低至 0.12 eV（即约 10 微米）时仍主导自由载流子的贡献。这种光谱响应使锑纳米结构能够展示光谱选择性和可调谐的纳米光子共振。首先，我们展示了锑纳米光栅在可见光到近红外的带间等离激元共振。其次，我们报道了纳米结构锑/介电/金属谐振腔在中红外的巨折射率介电共振。这些发现为优化的平面锑纳米设计开辟了道路，实现了可定制的光-物质相互作用，这将有助于在宽光谱范围内工作的集成数据、电信、医疗、光电和能量转换设备。
英文摘要
Semimetal elemental antimony (Sb) nanostructures show great potential for applications where nanophotonic properties play a key role, such as phase-change optical memories, non-linear optical elements, photothermal therapy agents, photodetectors and photocatalysts. However, designing advanced Sb-based photonic devices critically requires an accurate and reliable knowledge of the optical response of bulk and nanoscale Sb. Herein, we report for the first time a fully consistent and accurately measured dielectric function for Sb nanoscale films in a wide spectral range from the ultraviolet to the far infrared (4 - 0.04 eV, i.e. ~ 0.3 - 30 $μ$m), surpassing previous reports that explored a limited spectral range. It is found that the Sb spectral response is driven exclusively by giant interband transitions in the visible up to mid infrared (4 - 0.4 eV, i.e. ~ 0.3 - 3 $μ$m), and that their contribution dominates over that of free carriers down to 0.12 eV (i.e. ~ 10 $μ$m). Such spectral response enables Sb nanostructures to display spectrally selective and tunable nanophotonic resonances. First, we showcase interband plasmonic resonances in the visible-to-near infrared for Sb nanogratings. Second, we report giant refractive index dielectric resonances in the mid infrared for nanostructured Sb/dielectric/metal resonant cavities. These findings open a pathway to optimized planar Sb nanoscale designs enabling a tailored light-matter interaction, which will be useful for integrated data, telecom, medical, optoelectronic and energy conversion devices operating in a broad spectral range.
