Fig. 5. Progress towards lab-on-a-chip detector systems.

a Illustration of a waveguide-integrated hybrid nanophotonic biosensing platform. By harnessing excitons, plasmons, and phonon-polaritons in a wide range of vdW materials, we envision that researchers will be able to integrate light sources, mid-IR sensors, nano-tweezers, and detectors on a chip. Image credit: Daehan Yoo. b Monolithically integrated lab-on-a-chip chemical sensing platform based on a quantum cascade laser and detection coupled with a gold plasmonic waveguide. Reprinted from ref. ⁸⁴ with permission. c Waveguide-integrated SEIRA sensor. Five pairs of gold nanorods with a 30-nm gap were patterned on a silicon waveguide for SEIRA sensing of molecular monolayers. Reprinted from ref. ⁸⁵ with permission. d Waveguide-integrated black phosphorus photodetector.