Temperature dependence on the domain structure of epitaxial PbTiO3 films grown on single crystal substrates with different lattice parameters

Abstract

Epitaxial PbTiO3 (PTO) thin films were deposited on different single crystal (100)KTaO3 [KTO], (110)DyScO3 [DSO], (110) GdScO3 [GSO] and (001)SrTiO3 [STO] substrates. Temperature dependence of the lattice parameters and the domain structure showed a systematic change with misfit strains (Sm) of PTO films, explored by high-resolution X-ray diffraction measurements. Fully (001)-orientation films on STO and fully (100)-orientation films on KTO substrates were confirmed, and the elevated phase transition temperature (Tc) was confirmed in PTO films induced by both large compressive (STO) and tensile strains (KTO). While, for PTO films grown on GSO substrates with small tensile strains, Tc is similar to the powder data. And, ferroelastic domain structure changed from (100)-orientation to (100)/(001)-orientations was observed during decreased temperature. The temperature dependence of domain structures PTO films with the different Sm are in good agreement with thermodynamic calculation for the temperature–Sm diagram of ferroelastic domain structure.