Silicon Channeled Spectropolarimeter for On‐Chip Single‐Detector Stokes Spectroscopy

Abstract

Compact and low‐cost spectropolarimeters are desirable in many fields for probing the wavelength‐dependent polarization state of light. Conventional spectropolarimetry systems use bulky, free‐space optical components or require at least four spectrometers. Herein, a chip‐scale spectropolarimeter capable of reconstructing input Stokes spectrum with a single spectrometer is demonstrated. All the components, including a surface polarization splitter, a channeled spectrum generator, and a Vernier spectrometer, are monolithically integrated on a footprint of 0.3 mm × 1.5 mm. The device is implemented using a complementary metal oxide semiconductor (CMOS)‐compatible fabrication process and achieves a resolution of 0.1 nm across a wavelength range of 56 nm near 1550 nm. This work provides a path toward on‐chip, low‐cost Stokes spectroscopy.