Wave vector of a polariton mode

[skyboarder2]

Hey,
I'm looking for a method for calculating the wave vector of a polariton mode with a given frequency f knowing the static and high frequency dielectric constants of InP (\epsilon_st and \epsilon\infty) and the TO phonon frequency \upsilon_TO.
Thanks for your help!

S.

 

[phy127]

Hi,
I am also interested in polaritons, but on microcavity exciton-polaritons only. I believe you are asking about phonon-polaritons. Based on my understanding, the dispersion relation for polaritons, like any other materials, depend primarily on the dielectric function.
\frac{c^2 k^2}{\omega ^2}=\varepsilon (\omega )
where e(w) is the dielectric function. I really don't know if I'm helping but I think you need to know the whole dielectric function of the system, which can be derived theoretically. It would look like this,
\varepsilon (\omega )\approx \varepsilon _{0}+\frac{\Omega ^{2}}{\omega _{0}+\omega ^{2}}

Hope this helps.

 

[Dr Transport]

look for the lyddane-sachs-teller relation

 

[skyboarder2]

Thanks for your help