Strain-induced control of domain wall morphology in ultrathin PbTiO3 films

Ab initio effective Hamiltonian simulations reveal a strain-induced control of domain morphology in epitaxial PbTiO3 ultrathin films being under open-circuit electrical boundary conditions. More precisely, rather different out-of-plane domain structures are found to be the ground state, depending on the value of the misfit strain. Examples include domain walls lying in different crystallographic planes or even being wandering. Analysis of the computations allows us to reveal the precise interactions responsible for such strain-driven domain reorganization.