Plasmonic behavior in the far-infrared (IR) and terahertz (THz) ranges can facilitate a lot of applications in communication, imaging or sensing, security, and biomedical domains. However, simple scaling laws cannot be applied to design noble metal-based plasmonic systems operating at far-IR or THz frequencies. To overcome this issue, we numerically and experimentally explore the plasmonic properties in the spectral range between 25 and 40 μm (12 and 7.5 THz) of metal-insulator-metal (MIM) antennas made of InAsSb a highly Si-doped semiconductor. We demonstrate that these MIM antennas sustain a gap plasmon mode that is responsible for high light absorption. By tracking this peculiar plasmonic signature for various antennas' widths, we prove that Si-doped InAsSb microstructures realized on large areas by laser lithography and the wet etching process are a low cost, reproducible, and readily CMOS compatible approach.

中文翻译：

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基于高掺杂 InAsSb 的远红外范围金属-绝缘体-金属天线

远红外 (IR) 和太赫兹 (THz) 范围内的等离子体行为可以促进通信、成像或传感、安全和生物医学领域的许多应用。然而，简单的缩放定律不能应用于设计在远红外或太赫兹频率下运行的基于贵金属的等离子体系统。为了克服这个问题，我们通过数值和实验探索了由 InAsSb 一种高硅掺杂半导体制成的金属-绝缘体-金属 (MIM) 天线在 25 到 40 μm（12 到 7.5 THz）光谱范围内的等离子体特性。我们证明这些 MIM 天线维持负责高光吸收的间隙等离子体模式。通过跟踪各种天线宽度的这种奇特的等离子体特征，