Raman spectroscopy is a powerful technique that can be used to obtain detailed chemical information about a system without the need for chemical markers. It has been widely used for a variety of applications such as cancer diagnosis and material characterization. However, Raman scattering is a highly inefficient process, where only one in 10¹¹ scattered photons carry the needed information. Several methods have been developed to enhance this inherently weak effect, including surface enhanced Raman scattering and coherent anti-Stokes Raman scattering. These techniques suffer from drawbacks limiting their commercial use, such as the need for spatial localization of target molecules to a ‘hot spot’, or the need for complex laser systems. Here, we present a simple instrument to enhance spontaneous Raman scattering using elastic light scattering. Elastic scattering is used to substantially increase the interaction volume. Provided that the scattering medium exhibits very low absorption in the spectral range of interest, a large enhancement factor can be attained in a simple and inexpensive setting. In our experiments, we demonstrate an enhancement of 10⁷ in Raman signal intensity. The proposed novel device is equally applicable for analyzing solids, liquids, and gases.

Date Published: 4 March 2014
PDF: 6 pages
Proc. SPIE 8939, Biomedical Vibrational Spectroscopy VI: Advances in Research and Industry, 893909 (4 March 2014); doi: 10.1117/12.2040803

Published in SPIE Proceedings Vol. 8939:
Biomedical Vibrational Spectroscopy VI: Advances in Research and Industry
Anita Mahadevan-Jansen; Wolfgang Petrich, Editor(s)