Richard Clark wrote:
On Thu, 18 May 2006 19:01:58 -0500, Tom Ring
wrote:


I had not heard of the Stokes shift, nor the scattering you mentioned.
I have some looking up and reading to do. Which, of course, Cecil does
not, since it's not a Xerox moment.


Hi Tom,

It is pretty exotic, it only relates to radiation, reflection,
refraction, heat, and conduction, topics that are alien to discussion
here in more than TV Guide English it appears. Other difficult
concepts include linearity, coherence, mixing, and gain.

Stokes shift is the change in frequency due to the non-linear response
of a media to excitation. Typically the excitation is a photon
interacting with a phonon with radiation scattering following.
Injecting an electron (current) can achieve the same end. The effect
of power clamping in fiber optic transmission lines is due to SBS
(Stimulated Brillouin Scattering) threshold. I've been working with
this (Stokes and Anti-Stokes Shift) for some 20 years, and it fails
easy access through a copier.

The mention came only response to questions of linear response to what
at first glance would be a rather pedestrian transmission line
definition, but Glenn appears to have followed the clown instead of
pursuing his own question - he warned me it may have been pointless.

SBS and SRS (Stimulated Raman Scattering) would be suitable search
engine terms (esp. SBS threshold), but I warn you, they lead to
remarkably dense work where only one link in 20 will be accessible.

73's
Richard Clark, KB7QHC

Hi Richard,
Stokes' law and the Raman effect can be found in
physics texts dealing with quantum mechanics. Georg Joos, in
his book _Theoretical Physics_ deals with such things. The reading
is dense but the underlying concepts aren't too difficult. The
difficulty might lie in understanding how they apply to this
discussion.
73,
Tom Donaly, KA6RUH