We present new, to the best of our knowledge, large-scale, high-quality spectral filters operating in the long-wave infrared (LWIR) spectral region. We employ high-spatial resolution nanofabrication techniques to achieve large-area (${12}\;{{\rm mm}} \times 12\;{{\rm mm}}$) spectrally tunable notch filters. Filter operation is based on the guided-mode resonance effect. The device structure consists of a germanium waveguide grating on top of a zinc selenide substrate. The filters reflect the incident broadband light at one (or more) narrow spectral bands while fully transmitting the rest. We tune the reflected wavelength by tilting the filter. Filters based on one-dimensional gratings are polarization sensitive. We fabricate prototype filters and characterize their polarization dependence and spectral tuning performance using a tunable quantum cascade laser system that spans the $\sim{7 - 13}\;\unicode{x00B5}{\rm m}$ spectral band. We obtain an excellent agreement between the theoretical and experimental results.

中文翻译：

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用于长波红外区域的高质量大规模电子束写入谐振滤波器

据我们所知，我们将提供在长波红外（LWIR）光谱区域中运行的大规模，高质量光谱滤波器。我们采用高空间分辨率的纳米加工技术来实现大面积（$ {12} \; {{\ rm mm}} \ times 12 \; {{\ rm mm}} $）频谱可调陷波滤波器。滤波器操作基于引导模式共振效应。器件结构由硒化锌衬底顶部的锗波导光栅组成。滤光片在一个（或多个）窄光谱带反射入射的宽带光，而其余部分则完全透射。我们通过倾斜滤光片来调整反射波长。基于一维光栅的滤波器对偏振敏感。我们制造了原型滤波器，并使用可调谐量子级联激光系统表征了其偏振依赖性和光谱调谐性能，该系统跨越了\\ sim {7-13} \; \ unicode {x00B5} {\ rm m} $光谱带。我们在理论和实验结果之间取得了很好的一致性。