We report on a GaN/AlGaN quantum cascade detector operating in the terahertz spectral range. The device was grown by metal organic chemical vapor deposition on a c-sapphire substrate and relies on polar GaN/AlGaN step quantum wells. The active region thickness is in micrometer range. The structural, electrical, and optical investigations attest of high structural quality of the synthetized nitride material. The detector exhibits a peak photocurrent at 5.7 THz (23.6 meV) with a responsivity of 0.1 mA/W at 10 K under surface normal irradiation through a 10 μm period grating. The photocurrent persists up to 20 K.

中文翻译：

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基于极阶跃量子阱的 5.7 THz GaN/AlGaN 量子级联探测器

我们报告了在太赫兹光谱范围内运行的 GaN/AlGaN 量子级联探测器。该器件通过金属有机化学气相沉积在 c-蓝宝石衬底上生长，并依赖于极性 GaN/AlGaN 步进量子阱。有源区厚度在微米范围内。结构、电学和光学研究证明了合成氮化物材料的高结构质量。该检测器在 5.7 THz（23.6 meV）处表现出峰值光电流，在 10 K 下通过 10 μm 周期光栅进行表面法线照射时，响应率为 0.1 mA/W。光电流持续高达 20 K。