Stimulated Raman Scattering Spectroscopy

[oneilltn]

Has anyone read or seen any articles that might highlight the techniques of Stimulated Raman Scattering Spectroscopy? Or just any knowledge on the process they would be able to share? I am having a tough time getting a hold on the process and if anyone has any useful information or articles that might lay it out a bit more clearly that would be very helpful. Thank you.

 

[Andy Resnick]

Google returned 'About 427,000 results (0.24 seconds)', including numerous articles about the technique, for example:

http://www.utdallas.edu/~cantrell/ee6328/srs.pdf

and Bruker makes a line of instruments:

http://www.bruker.com/products/molecular-vibrational-spectroscopy/raman.html

can you be more specific in what you are looking for?

 

[Tony Campillo]

Frankly, Stimulated Raman Spectrosocpy is not a useful spectroscopic tool. The line/vibration with the highest gain reaches threshold first, reduces the overall gain of other lines and so dominates the specta. So instead of seeing a spectral fingerprint of all lines and species present, the spectrum consists of a single line (or often other lines associated with Stokes and anti-Stokes features of the majority species). For example, suppose one wished to monitor impurities in ethanol with SRS. Generally what you would see is only the 2928 cm-1 feature associated with the majority species ethanol and no sign of impurities.

Consequently, spontaneous Raman scattering spectroscopy remains a popular tool yielding an easily obtained fingerprint of all vibrations/species present. Occasionally, some nonlinear approaches like CARS (Coherent Anti-Stokes Raman Spectrosocpy) are used in special cases (as for example, when background light levels are a problem, say in a flame).

The closest spectroscopy related to SRS is cw coherent Raman gain spectroscopy popularized by Owyoung in the 70's (see for example, http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=1069760&url=http%3A%2F%2Fieeexplore.ieee.org%2Fiel5%2F3%2F22982%2F01069760.pdf%3Farnumber%3D1069760 ). It doesn't seem to be in use much nowadays, perhaps because of the need for several tunable lasers (too complex, expensive).

 

[Tony Campillo]

Here's some papers that may be interest that use femtosecond pulse technology to overcome the problem I described above. Technique is called impulsive SRS spectroscopy.

http://www.weizmann.ac.il/home/feyaron/PDFfiles/SPSRS.pdf

https://engineering.purdue.edu/~fsoptics/articles/Femtosecond_Multiple-Pulse-Weiner.pdf

http://www.google.com/patents/WO2011062842A1?cl=en

 

[oneilltn]

I am supposed to research this imaging method and give a short presentation on it for class and was looking to find any papers or articles that helped to lay out the process in a more basic manner, since I am having trouble comprehending the process. So anything that breaks down the method would be something helpful. Thanks for the help

 

[Tony Campillo]

There's quite a few SRS imaging papers that can be located using google. Several have pretty good diagrams showing schematically hown the imaging process works.

http://www.sciencemag.org/content/322/5909/1857.full.pdf

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3576036/

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3462359/

http://iopscience.iop.org/1367-2630/11/3/033026/pdf/1367-2630_11_3_033026.pdf

http://www.semrock.com/stimulated-raman-scattering-srs.aspx

http://www.ncbi.nlm.nih.gov/pubmed/22316340