Dielectric relaxation in charge-carrier dominated systems

The relaxation of charge carriers among traps may give rise to dielectric loss peak. The peak frequency depends on the depth of traps. The occupation of traps depends on injection of charge carriers from electrodes. If the concentration of injected charge carriers is larger than the concentration of the intrinsic charge then the occupation of traps is described by the quasi-steady-state Fermi level depending on the injection. The depolarisation phenomenon consists in the outflow of the excess charge in this case and the relaxation time turns out to be dependent on the concentration of traps. Experimental examples of inter-trap relaxations in low-molecular weight organic compounds are presented.