High dielectric tunability of KTa0.60Nb0.40O3 single crystal

The dielectric nonlinear behavior of KTa0.60Nb0.40O3 single crystal grown by the top-seeded solution growth method was studied. High dielectric tunability (77%) and low loss (2.3%) was obtained at 1 kHz and room temperature, indicating that the KTa0.60Nb0.40O3 crystal is an attractive candidate for tunable device applications. The dielectric nonlinear behavior was further studied in terms with the Landau-Ginzburg-Devonshire thermodynamic theory completed with the Langevin term. It is found that the extrinsic polarization plays a remarkable role in the dielectric nonlinear behavior and it gives an amount of 42.1% contribution to the dielectric tunability with E = 1 kV/mm. (C) 2013 AIP Publishing LLC.