June 5, 2017 – An Oak Ridge National Laboratory–led team discovered a link between electrochemistry at the surface and ferroelectricity within the bulk material of ultrathin crystalline films. The findings, published in Nature Physics, explain a decade of anomalous thin-film behavior observations and offers a new mode for control. “We show that surface chemistry can be a third method, besides using traditional substrate strain and octahedral rotation, to achieve similar effects for memories, tunneling junctions, memristors and neuromorphic computing,” ORNL’s Sergei Kalinin said. The research team will explore new opportunities for controlling ferroelectric materials. For example, because light couples weakly to ferroelectricity but strongly to surface chemistry, the discovery may accelerate designs of next-generation detectors and photovoltaics.
