Chip-Based Resonance Raman Spectroscopy Using Tantalum Pentoxide Waveguides

Blood analysis is an important diagnostic tool, as it provides a wealth of information about the patient's health. Raman spectroscopy is a promising tool for blood analysis, but widespread clinical application is limited by its low signal strength, as well as complex and costly instrumentation. The growing field of waveguide-based Raman spectroscopy tries to solve these challenges by working toward fully integrated Raman sensors with increased interaction areas. In this letter, we demonstrate resonance Raman measurements of hemoglobin, a crucial component of blood, at 532-nm excitation using a tantalum pentoxide (Ta2O5) waveguide platform. We have also characterized the background signal from Ta2O5 waveguide material when excited at 532 nm. In addition, we demonstrate spontaneous Raman measurements of isopropanol and methanol using the same platform. Our results suggest that Ta2O5 is a promising waveguide platform for resonance Raman spectroscopy at 532 nm and, in particular, for blood analysis.