Terahertz electro-optic properties of PbZr_(0.52)Ti_(0.48)O_3 and BaTiO_3 ferroelectric thin films

摘要

Electro-optic effects of PbZr_(0.52)Ti_(0.48)O_3 (PZT) and BaTiO_3 (BTO) ferroelectric thin films in the terahertz frequency range are studied with high-sensitive terahertz time-domain spectroscopy. A linear response of PZT film with the linear electro-optic coefficient r_c = 6.73 × 10~(11) m/V and a quadratic response of BTO film with the second-order electro-optic coefficient R_c = 1.42 × 10~(17) m~2/V~2 are observed at the frequency of 1 terahertz under the applied static electric field less than 80kV/cm. The calculation of r_c and R_c based on the Landau-Devonshire free energy theory explains the different electro-optic effects of PZT and BTO well.