Strain Engineering of Domain Coexistence in Epitaxial Lead-Titanite Thin Films

Phase and domain structures in ferroelectric materials play a vital role in determining their dielectric and piezoelectric properties. Ferroelectric thin films with coexisting multiple domains or phases often have fascinating high sensitivity and ultrahigh physical properties. However, the control of the coexisting multiple domains is still challenging, thus necessitating the theoretical prediction. Here, we studied the phase coexistence and the domain morphology of PbTiO3 epitaxial films by using a Landau–Devonshire phenomenological model and canonic statistical method. Results show that PbTiO3 films can exist in multiple domain structures that can be diversified by the substrates with different misfit strains. Experimental results for PbTiO3 epitaxial films on different substrates are in good accordance with the theoretical prediction, which shows an alternative way for further manipulation of the ferroelectric domain structures.11Ysciescopu