STUDY OF THE TRANSPORT-PROPERTIES OF POLYCRYSTALLINE DOLOMITE (CAMG(CO3)(2)) BY THE THERMALLY STIMULATED DEPOLARIZATION CURRENT TECHNIQUE

The thermally stimulated depolarization current (TSDC) technique is em ployed to study the transport phenomena in dolomite which is unstable at high temperatures. The spectrum of polycrystalline dolomite exhibit s a strong relaxation peak which reaches a maximum close to room tempe rature. The dependence of the data on the polarization conditions, the electrode material and the sample thickness suggests that the mechani sm responsible for the TSDC peak is related to space charge relaxation and that the polarization of the material is inhomogeneous, involving long distance free charge migration. A selective polarization mode wa s applied in order to sample the response components, while the partia l heating technique led to a temperature distribution of activation en ergy values. (C) 1997 Elsevier Science Ltd. All rights reserved.