Gamma ray irradiation effect on optical, dielectric, ferroelectric and ferroelectric fatigue properties of neodymium doped rubidium titanyl phosphate single crystal (Nd:RbTiOPO4)

Abstract

Neodymium doped rubidium titanyl phosphate single crystal was grown from the high-temperature flux technique. To investigate the material stability in the radiation background, for the first-time neodymium doped rubidium titanyl phosphate single crystal was subjected to gamma ray irradiation. After the irradiation of the 2.6-kGy gamma-radiation, the material’s optical and electrical properties were analyzed and the results have been compared to that of non irradiated Nd: RTP single crystal. A small absorption band was found in the visible region around 0.08 higher than the non -irradiated Nd: RTP single crystal and there is a small variations in the band gap energy, 3.61 eV for non -irradiated Nd: RTP single crystal and 3.54 eV for gamma irradiated Nd: RTP single crystal. The dielectric constant, dielectric loss, and AC conductivity was observed for non-irradiated and gamma irradiated Nd: RTP single crystals. The Gamma radiation irradiated Nd: RTP single crystal shows little higher value of dielectric constant, loss and conductivity around 0.07, 0.05 and 1.2 S/cm from the non irradiated sample respectively. From the ferroelectric studies there is an increase in polarization and coercive field were observed in the gamma-ray irradiated sample from that of non-irradiated Nd: RTP single crystal. This can be attributed to radiation-induced defects is local strains and movements of ions inside the crystal. Besides the Gamma irradiated sample shows fatigue free nature over the 5000 cyclic period. The gamma-ray induced a defect in material but not far away from application requirements and the radiation effect had been removed through the thermal annealing process.