Room temperature ferroelectricity of tetragonally strained SrTiO _3 thin films on single crystal Rh substrates

摘要

Epitaxial SrTiO _3 thin films were deposited on single crystalline Rh substrates by pulsed laser deposition. The tetragonally stained structure of the SrTiO _3 thin films with a c/a ratio of 1.04 was confirmed by x-ray diffraction experiments. The SrTiO _3 thin films exhibited good ferroelectric properties with a high remanent polarization (2P _r) of 8 μC/cm ~2 and a canonical ferroelectric piezoresponse hysteresis loop at room temperature. We estimated a high activation electric field of about 6.4 MV/cm for domain wall creeping. This activation electric field is higher than that of typical ferroelectric materials such as PbTiO _3.