Changes in permittivity of KTa1-xNbxO3 crystals induced by electron injection in relation to nonlinear dielectric response

We observed large increases in the capacitance of a KTa1-xNbxO3 (KTN) optical beam deflector that were induced by electron injection. The increases were not caused by changes in the electrode interface but rather by changes in the permittivity of the bulk crystal. In the paraelectric phase, the KTN crystal exhibited a nonlinear dielectric response with double hysteresis loops in the D-E curves. We ascribed the permittivity change to this nonlinear phenomenon. (C) 2014 The Japan Society of Applied Physics