Register to reply

Relationship between the refractive index and absorption

by asdfghhjkl
Tags: absorption, index, refractive, relationship
Share this thread:
asdfghhjkl
#1
Nov14-13, 06:12 AM
P: 5
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 :)
Phys.Org News Partner Physics news on Phys.org
Step lightly: All-optical transistor triggered by single photon promises advances in quantum applications
The unifying framework of symmetry reveals properties of a broad range of physical systems
What time is it in the universe?
adjacent
#2
Nov14-13, 06:34 AM
PF Gold
adjacent's Avatar
P: 1,496
Quote Quote by asdfghhjkl View Post
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.
asdfghhjkl
#3
Nov14-13, 06:38 AM
P: 5
Ok, thank you.

adjacent
#4
Nov14-13, 06:49 AM
PF Gold
adjacent's Avatar
P: 1,496
Relationship between the refractive index and absorption

Quote Quote by asdfghhjkl View Post
Ok, thank you.
Please give thanks by using the "thanks" button.
DrDu
#5
Nov14-13, 07:01 AM
Sci Advisor
P: 3,593
There is a relation between absorption and refractive index which is known as Kramers Kronig relation:
http://www.rp-photonics.com/kramers_...relations.html
However, to deduce the one from the other, you need to know the absorption or refractive index ideally for all frequencies.
Andy Resnick
#6
Nov14-13, 08:23 AM
Sci Advisor
P: 5,523
Quote Quote by asdfghhjkl View Post
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.
Claude Bile
#7
Nov15-13, 07:44 AM
Sci Advisor
P: 1,477
The intensity-dependent component of the refractive index is known as the Kerr nonlinearity (real part) and saturable absorption (imaginary part).

Claude.


Register to reply

Related Discussions
Dielectric constant refractive index relationship General Physics 3
Relationship between density and refractive index of a medium Classical Physics 1
Refractive index of gold? (& negative refractive index, + surface plasmon resonance?) Atomic, Solid State, Comp. Physics 3
Relationship between Refractive index and Inpedance General Physics 5
Refractive index Introductory Physics Homework 1