At higher frequencies, the current in the metallic wire is not uniformly distributed over the whole area of cross section rather it flows more on surface of the conductor. This is called skin effect. The current density decreases exponentially from the surface towards the axis of the wire. The thickness at which current density becomes 1/e of the value at the surface is called skin depth. It depends on the conductivity of the metal and frequency of a.c. More frequency of a.c., smaller is skin depth.Higher the conductivity, smaller the skin depth.It also depends on the magnetic permeability of the medium.For detailed formule of skin depth see Wikipedia on skin effect.
Skin effect has been studied in semiconductors also at microwave frequencies.You can make Google research on skin effect in semiconductors then there are many research papers which relate skin effect to electrical conductivity. Since conductivity in semiconductors depends strongly on temperature and optical band gap, one can find a correlation with optical properties but it will be an indirect relation as skin effect is related to the electrical transport in metals and semiconductors.
It is a very good question and good discussion from Prof. Dr. @Dr A. Kumar and Prof. Dr. @ Salah Mahrous. It is very informative and interesting. Always you are innovator.