It was shown that 2 types of polariton were localized at dislocations in ionic crystals. Dispersion equations were derived for the localized polaritons, and the dependence of the oscillation amplitude upon the distance to the dislocation was determined.

Localization of Polaritons Close to Dislocations in Ionic Crystals. S.G.Gestrin: Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, 1996, 39[10], 45-50 (Russian Physics Journal, 1996, 39[10], 938-43)