The controllable anisotropic characters in solid solution ferroelectrics
Composition gradient (CG) has significant influences on the polarization states by bringing in flexoelectric and gradient energy, which induces anisotropic macroscopic properties. In this work we designed and grown KTa1-xNbxO3 (KTN) single crystals with anisotropic CGs. The results reveal that the anisotropic CGS induce anisotropic properties, the larger CG corresponds to the smaller dielectric permittivity, and more ordered and preferred orientation of spontaneous polarization. Besides, increasing CG of KTN single crystal, internal fields (Ein) will be generated, which is the origin of the polarization orientation and order degree along Ein direction. In addition, results also show that the anisotropic CGs of KTN are controllable, which provides a potential alternative way to control the anisotropic characteristics of KTN.