ArticleWang RV, Fong DD, Jiang F, Highland MJ, Fuoss PH, Thompson C, Kolpak AM, Eastman JA, Streiffer SK, Rappe AM, Stephenson GB.
Phys Rev Lett. 2009 Jan 30;102(4):047601.
According to recent experiments and predictions, the orientation of the polarization at the surface of a ferroelectric material can affect its surface chemistry. Here we demonstrate the converse effect: the chemical environment can control the polarization orientation in a ferroelectric film. In situ synchrotron x-ray scattering measurements show that high or low oxygen partial pressure induces outward or inward polarization, respectively, in an ultrathin PbTiO3 film. Ab initio calculations provide insight into surface structure changes observed during chemical switching.