Time-Resolved Suppression of Fluorescence in Raman Spectrometry By Continuous Wave Laser Amplitude Modulation and Phase-Sensitive Detection

Abstract
Raman spectroscopy applied to biological systems is often dominated by interfering fluorescence background. In this report Raman scattering of benzene in the presence of strong fluorescence was obtained via phase sensitive detection upon sinusoidally modulating the continous wave laser beam at tens of MHz. Extended detectability of the 992 cm−1 frequency was obtained, but the signal enhancement is greatly dependent on the experimental measuring time.