  Blood analysis is an important diagnostic tool, as it provides a wealth of
information about the patient health. Raman spectroscopy is a promising tool in
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 towards fully integrated Raman sensors with increased interaction
areas. In this work, we demonstrate on-chip 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 iso-propanol 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.
