CMOS-Compatible High Resolution Spatial Heterodyne Spectrometer Based on Si3N4/SiO2 Waveguide

We experimentally demonstrated an integrated spatial heterodyne spectrometer fabricated on double-strip TriPleX waveguide technology. The TriPleX waveguide has a very low loss and tight bend so that the spectrometer realizes a high resolution of 0.023 nm across a wavelength range of 0.184 nm at 1550 nm in a small footprint of 4 mm × 8 mm. Moreover, the proposed integrated spectrometer combines the advantages of the planar lightwave circuit waveguide technology-based spectrometer and silicon-on-insulator technology-based spectrometer. The former has a very high resolution and relative high temperature stability while the latter can be implemented into a compact size based on CMOS-compatible standard technology. Besides, the wide transparency waveband of TriPleX waveguide platform makes it possible for the spatial heterodyne spectrometer to extend the working wavelength to the waveband of visible light and near infrared.