Lab-on-a-chip optical biosensor platform: a micro-ring resonator integrated with a near-infrared Fourier transform spectrometer

Abstract

In this paper, we demonstrated the design and experimental results of the near-infrared lab-on-a-chip optical biosensor platform that monolithically integrates the MRR and the on-chip spectrometer on the silicon-on-insulator (SOI) wafer, which can eliminate the external optical spectrum analyzer for scanning the wavelength spectrum. The symmetric add-drop MRR biosensor is designed to have a free spectral range (FSR) of ∼19 nm and a bulk sensitivity of ∼73 nm/RIU; then the drop-port output resonance peaks are reconstructed from the integrated spatial-heterodyne Fourier transform spectrometer (SHFTS) with the spectral resolution of ∼3.1 nm and the bandwidth of ∼50 nm, which results in the limit of detection of 0.042 RIU.