Thermally stimulated depolarization phenomena in LiF:${\mathrm{Ca}}^{2+}$ crystals

The thermally-stimulated-depolarization-current method is used in order to characterize the dielectric relaxation processes in LiF crystals doped with ${\mathrm{Ca}}^{2+}$ impurities. Results on as-grown samples indicate a space charge and/or an interfacial polarization phenomenon. Thermal perturbation is employed to release free impurity-cation vacancy dipoles. The subsequent bands are critically visualized and one of them is attributed to jumps of the bound-cation vacancy via nearest-neighbor paths.