Extreme miniaturization of infrared spectrometers is critical for their integration into next-generation consumer electronics, wearables and ultrasmall satellites. In the infrared, there is a necessary compromise between high spectral bandwidth and high spectral resolution when miniaturizing dispersive elements, narrow band-pass filters and reconstructive spectrometers. Fourier-transform spectrometers are known for their large bandwidth and high spectral resolution in the infrared; however, they have not been fully miniaturized. Waveguide-based Fourier-transform spectrometers offer a low device footprint, but rely on an external imaging sensor such as bulky and expensive InGaAs cameras. Here we demonstrate a proof-of-concept miniaturized Fourier-transform waveguide spectrometer that incorporates a subwavelength and complementary-metal–oxide–semiconductor-compatible colloidal quantum dot photodetector as a light sensor. The resulting spectrometer exhibits a large spectral bandwidth and moderate spectral resolution of 50 cm⁻¹ at a total active spectrometer volume below 100 μm × 100 μm × 100 μm. This ultracompact spectrometer design allows the integration of optical/analytical measurement instruments into consumer electronics and space devices.

红外光谱仪的极端小型化对于将其集成到下一代消费电子产品、可穿戴设备和超小型卫星中至关重要。在红外波段，在小型化色散元件、窄带通滤波器和重建光谱仪时，需要在高光谱带宽和高光谱分辨率之间做出折衷。傅立叶变换光谱仪以其在红外线的大带宽和高光谱分辨率而著称。然而，它们还没有完全小型化。基于波导的傅里叶变换光谱仪设备占地面积小，但依赖于外部成像传感器，例如笨重且昂贵的 InGaAs 相机。在这里，我们展示了一种概念验证小型傅里叶变换波导光谱仪，它结合了亚波长和互补金属氧化物半导体兼容的胶体量子点光电探测器作为光传感器。由此产生的光谱仪具有大光谱带宽和 50 cm 的中等光谱分辨率^-1在总活性光谱仪体积低于 100 μm × 100 μm × 100 μm 时。这种超紧凑的光谱仪设计允许将光学/分析测量仪器集成到消费电子产品和空间设备中。