Movement of charge carriers in lossy dielectrics

The accepted analysis of the movement of thermal charge carriers such as electrons and ions in solids with finite dielectric losses does not take into account the inevitable energy losses arising from the transient polarisation of the medium. An analysis taking this into account leads to the concept of the dielectric drag force which may cause localisation of free electrons and which may produce instabilities, in view of the fact that the magnitude of this force decreases with increasing velocity of the charge. These features may explain some aspects of the observed behaviour of dielectrics.