Similarity in the critical thicknesses for superconductivity and ferroelectricity in strained SrTiO3films

Abstract

The possible connection between superconductivity and polar order in SrTiO3has been discussed extensively in the recent literature. Here, the thickness dependence of the superconducting and ferroelectric transitions in strained, epitaxial films of SrTiO3films is studied. Both superconductivity and ferroelectricity are absent in thinner films (25 nm and below). We discuss the possible origins of the thickness dependence of both phenomena.