A Single Waveguide Spectrometer via Defect Scattering

Miniaturized spectrometers show great application potential in biology, medicine, astronomy and so on. However, it is still challenging to obtain broadband spectrum and high spectral resolution simultaneously with limited size. In this study, we proposed a single waveguide spectrometer based on light scattering of the defects buried in the waveguide. The detections of the scattering light are set on the upper surface of the waveguide, as a result, tremendous detection channels can be realized even within a small structure size, which makes simultaneously high resolution and broad bandwidth detection achievable. Simulation studies show that this kind of spectrometer can exhibits an impressive bandwidth of 1000 nm, ranging from 600 to 1600 nm. Additionally, a resolution of 0.2 nm is achieved within the range of 850 to 852 nm through fine sampling. The influence factors of the performance of the spectrometer is also studied. This work provides the possibility of achieving on-chip, high-resolution, and wide-bandwidth spectrometers.