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Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
Published on: April 28, 2016
Direct measurement of resonance Raman spectra and cross sections by a polarization difference technique
Eric C Le Ru1, Lina C Schroeter, Pablo G Etchegoin
1The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6140, New Zealand. eric.leru@vuw.ac.nz
Analytical Chemistry
|May 11, 2012
Summary
This study introduces a new polarization-difference method to measure resonant Raman (RR) spectra using standard equipment. This technique overcomes fluorescence interference, making RR spectroscopy more accessible for analytical chemistry and biology applications.
Area of Science:
- Analytical Chemistry
- Spectroscopy
- Biophysics
Background:
- Resonant Raman (RR) spectroscopy offers valuable insights but is hindered by strong fluorescence backgrounds.
- Conventional RR measurements often necessitate complex, picosecond-time-resolved experimental setups.
- Fluorophores typically overwhelm RR signals, posing a significant experimental challenge.
Purpose of the Study:
- To develop a simplified method for measuring RR spectra and cross sections.
- To enable RR spectroscopy using standard Raman instrumentation.
- To overcome the limitations imposed by fluorescence interference in RR measurements.
Main Methods:
- A novel polarization-difference technique is presented.
- The method utilizes standard Raman spectroscopy setups with continuous wave excitation and CCD detection.
- Applied to fluorescent dyes like Nile Blue and rhodamine 6G under resonant excitation.
Main Results:
- Successful measurement of RR spectra and cross sections for Nile Blue and rhodamine 6G.
- Demonstration that RR spectroscopy can be performed without specialized time-resolved equipment.
- Significant reduction or elimination of fluorescence background interference.
Conclusions:
- The developed polarization-difference method simplifies RR spectroscopy.
- This approach allows routine measurement and study of RR spectra with conventional Raman systems.
- The findings pave the way for broader adoption of RR spectroscopy in various scientific fields.
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