Modeling of a Waveguide-Based UV-VIS-IR Spectrometer Based on a Lateral (In,Ga)N Alloy Gradient

The author presents the simulation and modeling of a waveguide-based ultracompact spectrometer for the near-ultraviolet through visible to infrared spectral range based on a lateral material gradient of InxGa1-xN from GaN to InN. Using reasonable material parameters from the literature, the reconstruction of a model spectrum in the range 0.8-3.5 eV is simulated for a lateral gradient from x = 0 to x = 1. The experimental realization of such spectrometer could drastically simplify confocal scanning microscopy and make spectral analysis and hyperspectral imaging available in hand-held and smartphone devices.