Description of the wavevector dispersion of surface plasmon-phonon-polaritons

We reported here the results of the calculations of wavevector dispersion of oscillations frequencies, $\omega'(k)$, and damping $\omega''(k)$ of the surface plasmon phonon polaritons (\mbox{SPPhP}) for the heavy-doped GaN sample. We showed that $\omega'(k)$- dependence consists of the three branches with the specific anticrossing behavior due to the interaction of surface plasmon polariton (SPP) with surface phonon polariton(SPhP). The strong renormalization of the damping $\omega''(k)$ in the vicinity of the anticrossing region was found. The obtained dispersions of the $\omega'(k)$ and $\omega''(k)$ were applied for the analytical analysis of exact electrodynamic simulation of the resonant behavior of the reflectivity spectrum of the n-GaN grating.