Recent advancements in the periodic poling and characterization of RTA and its isomorphs

An investigation of the electric field poling characteristics of RTA, KTA, CTA, and mixed crystals thereof has revealed a number of behaviors, which vary considerably among the arsenates. Sample crystals were studied using piezoelectric mapping, impedance spectroscopy, transient charge transfer measurements and hysteresis loop analysis. Measurements were carried out over temperatures ranging from 20 degree(s)C to 400 degree(s)C. Both parallel plate and lithographically patterned periodic structures were used in this study. Large differences in electrical impedance, coercive field, and hysteresis were observed for various compositions and temperatures. These behaviors have profound implications with regard to the formation of periodically inverted ferroelectric domains for nonlinear optical applications. Tentative theories are presented to explain the differences in terms of crystal structure. Several periodically poled devices were fabricated from the arsenates and operated satisfactorily as Nd:YAG pumped near IR optical parametric oscillators.