Abstract

Spectroscopic identification of particles in a flowing aerosol environment has been challenging due to the inherently short time scales needed to generate a spectrum. Traditional information rich Raman scattering requires long collection times, making it impractical in a complex aerosol system. We have overcome this difficulty by using a single-shot technique for chemical identification, multiplex coherent anti-Stokes Raman spectroscopy (MCARS). MCARS has been shown to generate a complete Raman spectrum of individual aerosol particles using a single laser source divided into two components: an ultrabroadband pulse to coherently drive multiple molecular vibrations simultaneously (830-1000nm) and a narrow probe pulse (785nm). In this paper, we present MCARS spectra obtained from various aerosol species of interest. In addition, analytical removal of the non-resonant background via complex spectral filtering significantly improves MCARS ability to accurately identify species.

© 2016 Optical Society of America