Relationship between the refractive index and absorption

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asdfghhjkl
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Hello,

I was wondering is there a relation between the refractive index of the material and the amount of light the material absorbs (e.g. the higher n means higher absorption)? If so what is then a relation between the intensity of the light and the refractive index?

p.s. I am trying to apply this to some geological thin section observations, thus a simple explanation would be appreciated.

Thank you :)
 
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asdfghhjkl said:
Hello,

I was wondering is there a relation between the refractive index of the material and the amount of light the material absorbs (e.g. the higher n means higher absorption)? If so what is then a relation between the intensity of the light and the refractive index?

p.s. I am trying to apply this to some geological thin section observations, thus a simple explanation would be appreciated.

Thank you :)
There is no relation between the intensity of light and the refractive index.Refractive index depends on the speed of light through the medium.It varies with wavelength too.
 
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asdfghhjkl said:
Ok, thank you.
Please give thanks by using the "thanks" button. :biggrin:
 
asdfghhjkl said:
Hello,

I was wondering is there a relation between the refractive index of the material and the amount of light the material absorbs (e.g. the higher n means higher absorption)? If so what is then a relation between the intensity of the light and the refractive index?

Echoing DrDu, absorption is often modeled by allowing the refractive index to be complex-valued (say n = η + iκ) the real part η is the 'refractive' component and the imaginary part κ the 'absorption' component. The components are not independent but related through the Kramers-Kronig relation.
 
The intensity-dependent component of the refractive index is known as the Kerr nonlinearity (real part) and saturable absorption (imaginary part).

Claude.