Scattering from lossy medium whose refractive index is unity

AI Thread Summary
A thin transparent plate with a refractive index equal to air but with a small loss can scatter light when a laser beam passes through it at an acute angle. The discussion explores whether light can be scattered towards an unexpected direction, specifically the upper right, despite the plate's refractive index matching that of air. The concept of scattering in this context is linked to the loss component, which may cause refraction-like bending of the light. The conversation suggests that while total internal reflection typically confines light within a specific plane, the unique properties of the plate could allow for unconventional scattering. Further reading on this phenomenon is encouraged to understand the underlying mechanisms better.
Swamp Thing
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Consider a thin transparent plate surrounded by air. The plate's refractive index is exactly the same as the air's, but it does have a small loss (say of the order of 1%).

Let the plate be vertical and normal to our "page" or your computer screen. A laser beam passes through the plate at an acute angle such as 5 degrees, say from the lower right to the upper left.

Now is there any mechanism in this system by which some of the light would be scattered towards the upper right? (FWIW, I arrived at this conjecture while following some train of thought that probably wouldn't interest anyone here).

If there is such a process, where can I read more about it? Does it have a name? Would the scattered energy form a beam similar in width to the incident one?
 
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For an absorptive material, the index of refraction becomes a complex quantity. Nevertheless it won't lead to scattering out of the plane defined by the normal to the surface and the incidence vector.
 
Thank you!
In my post, the question is about scattering within (consistent with) the constraint that you specified, but in a direction that is still counter intuitive. The direction I am asking about is similar to total internal reflection but with refractive index being the same as air.

You note that absorption is included in a complex coefficient -- so if I understand correctly, the loss component can result in refraction-like bending?
 
Swamp Thing said:
You note that absorption is included in a complex coefficient -- so if I understand correctly, the loss component can result in refraction-like bending?
Yes
 
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