sorry. could you please explain more. If you have an incident wave on a multi-layered media with definite propagation constant, then  transverse component of the wave in each layer is the same by the phase matching and so the normal component in the layer n is just

sqrt(k0^2*eps_n*mu_n-beta_t) where beta_t is the transverse propagation constant.

I hope it help.

Hello,

This is such a good question in case of propagation in multilayer media. Before measuring the values, first diagnose the epsilon and mue for all materials you have, because they will create surface wave or surface plasmonic wave between two layer of different materials. Now, electromagnetic wave has two components of normal and transverse in case of electric and magnetic fields, so that we have two components of phase propagation constant. now, one way to calculate it, by measuring the phase velocity or dispersion characteristics of wave and other way first calculate gamma and then by use of this calculate beta.

I am sending one paper, which might be helpful for you.

Thanks,

Some additional information is needed. The dependence on the geometry and layer properties is very strong. Generally, the type of the wave and the direction of wave propagation can be expressed by the wave vector components and the electromagnetic field components. Then from the Maxwell's equations in appropriate geometry you can obtain the wave equation and with corresponding boundary conditions you can find all necessary information. But often the final relations are transcendent equations and need numerical calculation.

Thank you all for your answers,

I have attached here a 4-page IEEE paper, in the second page the author defined kiz as the normal component of the propagation constant. I have highlighted the sentence with a yellow color. I do not know how the authors calculate it. Please, your help is very necessary!