Hagen–Rubens relation
Appearance
In optics, the Hagen–Rubens relation (or Hagen–Rubens formula) is a relation between the coefficient of reflection and the conductivity for materials that are good conductors.[1] The relation states that for solids where the contribution of the dielectric constant to the index of refraction is negligible, the reflection coefficient can be written as (in SI Units):[2]
where is the frequency of observation, is the conductivity, and is the vacuum permittivity.
The relation is named after German physicists Ernst Bessel Hagen and Heinrich Rubens who discovered it in 1903.[3]
References
- ^ Ziman, J.M. (1985). Principles of the theory of solids (2nd ed.). Cambridge: Cambridge University Press. ISBN 0521297338.
- ^ Hummel, Rolf E. Electronic properties of materials (4th ed.). New York: Springer. ISBN 1441981640.
- ^ Silveira, F. E. M.; Kurcbart, S. M. (1 May 2010). "Hagen-Rubens relation beyond far-infrared region". EPL. 90 (4): 44004. Bibcode:2010EL.....9044004S. doi:10.1209/0295-5075/90/44004. Retrieved 15 April 2013.