PbTiO3 thin films were epitaxially grown on (001) KTaO3 single crystal substrates by metalorganic chemical vapor deposition. The coherent epitaxial growth introduced a large in-plane tensile strain to the PbTiO3 film. This tensile strain increased T-C and directed the polarization to one of the in-plane < 100 > axes below T-C, resulting in the formation of perfect a(1)/a(2)/a(1)/a(2) domain structure. We found that the polar distortion is appreciably suppressed in such a(1)/a(2)/a(1)/a(2) domain structure while T-C is enhanced due to the strain. (C) 2015 AIP Publishing LLC.