Talk:Raman scattering

message: Is Raman scattering a 2nd or 3rd order effect?  It says here it's 2nd order, but I was under the impression it was 3rd order.  (If it can happen in symmetric materials, then it must be 3rd order.)
Raman scattering unless it is stimulated is a linear optical effect!
**Raman scattering is a third order effect.  It occurs in nonisotropic and isotropic medium.
**see for instance "Quantum Electronics" by Amnon Yariv
Most Raman is first order, the Raman scattering increases lineraly with the excitation intensity! You need second order pertubation theory to describe within quantum mechanics and there are two photons and one lattice (or molecular) vibration involved, but it is still first order. However, when you try really hard you can get second and third order Raman signals and coherent anti-stokes Raman scattering (CARS) is third order. Grmf
Then i delete the statement about Raman beeing third order, see e.g. D. A. Long, Raman Spectroscopy (McGraw-Hill, 1977). There is lots which could be improved in the article Grmf
Raman scattering is a third order effect.  See page 261 of Principles of Nonlinear Optical Spectroscopy by Shaul Mukamel 1995.  Any statement refering to it as a first order effect is either wrong, or a limited classical description.  Since the output frequency differs from the input frequency, it cannot be first order.  Secondly, it happens in symmetric materials, and is therefore not second order.  Writting a Feynman diagram, or using a wave mixing energy level (WMEL) diagram shows that it is a third order effect.  The statement that "most raman is first order" makes no sense in a quantum mechanical frame.  CARS, stimulated Raman, and your normal Raman scattering experiment differ in how many excitation lasers versus vacuum photons are used (ignoring phase matching, naturally).  While looking at how the signal scales with respect to an input laser can be used as an fair guide to determine the order of an effect classically, one cannot ignore vacuum photons for a rigorous treatment.  Nmathew 18:02, 18 April 2007 (UTC)
thread_title:  2nd or 3rd order? 

message: It should be mentioned the DTS (Distributed Temperature Sensing) in which the Stokes and the anti-Stokes Raman scattering are compared in a SRS system (only one of them is temperature-dependent, I can't remember which). This is used for measuring temperature along electrical cables and oil wells, early fire detection as well as many other applications.
Another new use for stimulated raman scattering is in-vivo video microscopy. This just a news article: http://www.eurekalert.org/pub_releases/2010-12/hu-nmt120110.php, the original journal article's citation is "Science  3 December 2010: Vol. 330 no. 6009 pp. 1368-1370 DOI: 10.1126/science.1197236 " (I'm relatively new to authoring so I'm unsure how to proceed) Falconerd (talk) 02:45, 7 December 2010 (UTC)
thread_title:  Uses of Raman Effect 

message: It sounds like this effect can have a directional bias (light is not scattered in all directions equally, without regard to the direction of the incoming radiation).  It would be interesting to get details on that and also have a diagram illustrating it.
The Raman effect has indeed a directional bias: the intensity of Raman scattering depends on the scattering angle (and as a matter of fact, the polarization state of the scattered light also depends on the scattering angle). However, unlike for Rayleigh scattering, no simple formula can be found that describes this dependence in all situations. The precise form of the dependence varies with kind of transition that is taking place and with the polarization states. However, I don't know what is appropriate to add to the Wikipedia article for this point. More information can be found in following reference: 
"The Raman Effect, A Unified Treatment of the Theory of Raman Scattering by Molecules" by Derek A. Long (, DOI 10.1002/0470845767). 134.184.47.51 (talk) 11:42, 2 April 2013 (UTC)
thread_title:  Directional bias 

message: Maybe it should be deleted: http://www.onforum.com/tutorials/acrobat/raman.pdf does not work, it does not send you to a Raman Scattering Pdf.  —Preceding unsigned comment added by 193.147.160.146 (talk) 13:45, 13 November 2007 (UTC)
thread_title: External link does not work

message: "In 1922, Indian physicist C. V. Raman published his work..." - is it necessary to emphesise that he was Indian? This never done for British, German, American physicists, etc., and it's inconsistent with, for example, Thomson scattering ("... first explained by the physicist J.J. Thomson"). The emphasis on his nationality seems to imply that prominent Indian physicists are uncommon, which is arguably not the case.
I'm not Indian by the way, so this isn't a Nationalistic chip-on-the-shoulder. I just like consistency :D
155.198.208.29 (talk) 12:04, 5 March 2010 (UTC)
thread_title:  INDIAN Physicist

message: Please write something about anti-Raman scattering and inverse Raman scattering. Lorem Ip (talk) 23:20, 14 April 2011 (UTC)
replies: text: The latter article has now been merged in, resolving that issue. Klbrain (talk) 11:07, 25 November 2017 (UTC)
thread_title:  [[Anti-Raman scattering]] and [[inverse Raman scattering]] 

message: I am the program coordinator of the ACS-National Historic Chemical Landmarks program. I have updated the references to ACS-NHCL web content, as those pages are being replaced. KLindblom (talk) 21:50, 6 June 2012 (UTC)
thread_title: Update External Link

message: Particle nature or wave nature Samir yogi (talk) 16:35, 19 August 2016 (UTC)
thread_title:  Nature 

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thread_title:  External links modified (January 2018) 

message: In Rechenberg's bio of Heisenberg, he cites Heisenberg referring to a 1926 "wager" (unclear if it was formally one or not) about an experiment on (what was to be known as) Raman scattering that would decide between Schrodinger's then-current interpretation and Heisenberg's -- in the context of Schrodinger and Wien very publicly crowing that Heisenberg's matrix mechanics was now obsolete; I'm nowhere learned enough to explain how the Raman / Krishan 1928 work resolved this, but I'm tempted to nevertheless add a blurb to the History section, unless there are objections.
Would also love any additional context here; we'd obviously not want an extended aside on the wave/matrix mechanics controversy, but the idea that this result helped to conclusively stop the reactionary impulses to turn the clock back on quantum theory feels both relevant and encyclopedic.
Any thoughts? ShadyNorthAmericanIPs (talk) 16:25, 20 August 2023 (UTC)
thread_title:  Heisenberg-Schrodinger "wager"