Re: [Phys-L] FTIR w/ water

[Bernard Cleyet <bernardcleyet@redshift.com>]

Note:   FTIR is not Fourier Transform IR.  It’s Frustrated Total Internal Reflection.


On 2015, Apr 23, , at 10:35, Paul Nord <paul.nord@valpo.edu> wrote:

> Really interesting question, Bernard.
>
> Are you suggesting using a ripple tank to demonstrate interferometry?

Nope.  


> Do you have a web link for those references?

Curiously, my library, as rather extensive, gave a much better result than a usual webb search.  Note ref’s below.  

> That sounds like a fun build.  I'm not sure what you do for a partially
> reflective surface in a ripple tank.

A change in speed due to a change in water depth causes refraction (if not normal) and reflection.  Why not as described by Fresnel?  Only S polarization tho?  This is how FTIR is shown.  

bc,  taking two wax prisms (65 pounds), for a student’s project, to SoCal AAPT meeting.

p.s.  I didn’t cheque Feynman et alii, —wouldn’t be surprised if they also gave water homology.  More:  

Most interesting is anomalous dispersion. The app. is a resonant slab and a sweep microwave source.  This is described, rather sketchily, by one of the Bell Labs teaching pamphlets.  

Here’s using split ring resonators (The bell Labs was simply wires, slanted WRT the polarization, so not so very absorbing.)    


Observation of Wave Packet Distortion during a Negative-Group-Velocity Transmission : Scientific Reports : Nature Publishing Group

http://www.nature.com/srep/2015/150129/srep08100/full/srep08100.html  


I’ve not read it carefully, so only think it “follows” the simple Drude-Lorentz theory.  



> Paul
>
>
> On Thu, Apr 23, 2015 at 3:03 AM, Bernard Cleyet <bernardcleyet@redshift.com>
> wrote:
>
> > Anyway, back to the ripple tank:  Anyone done FTIR? — Seems to me rather
> > easy, yet never seen any description.
> >
> > Wrong!   Fig. 5.23 Krane 2nd ed.
> >
> > Even Eisberg and Resnick  Fig. 6.18    Fig. 6.17 shows the evanescent wave!
> >
> > bc  gave up too soon and is embarrassed
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