Thermally Stimulated Depolarization Currents in TGS Crystals with Impurities and Radiation Defects under Stepwise Heating

Abstract

Thermally stimulated depolarization currents (TSDC) of triglycine sulfate (TGS) single crystals, which are pure, $$\gamma$$ -radiated and doped with Cr $${}^{3+}$$ ions, have been studied. When thousandths of a weight percent of interstitial impurities (Cr, Cu, and Fe) are introduced into the lattice of TGS single crystals at the growth stage, the domain structure stabilizes (monodomainization) and the region of the polar phase expands (up to $$T_{\textrm{M}}\sim 110^{\circ}$$ C), while the analogy of the dielectric response at the Curie point $$T_{\textrm{C}}\sim 49.7^{\circ}$$ C is preserved. These effects are observed on the TSDC curves as a peak near $$T_{\textrm{C}}$$ and additional diffuse anomalies near $$T_{\textrm{M}}$$ . Similar phenomena take place in TGS crystals irradiated with $$\gamma$$ -rays in the presence of a polarizing constant electric field. These anomalies are probably due to changes in the energy of protons during their jump-like transitions to a higher energy level in the double-well potential of a hydrogen bond.