Switchable polarization makes ferroelectrics a critical component in memories, actuators and electro-optic devices, and potential candidates for nanoelectronics. Although many studies of ferroelectric switching have been undertaken, much remains to be understood about switching in complex domain structures and in devices. In this work, a combination of thin-film epitaxy, macro- and nanoscale property and switching characterization, and molecular dynamics simulations are used to elucidate the nature of switching in PbZr0.2Ti0.8O3 thin films. Differences are demonstrated between (001)-/(101)- and (111)-oriented films, with the latter exhibiting complex, nanotwinned ferroelectric domain structures with high densities of 90° domain walls and considerably broadened switching characteristics. Molecular dynamics simulations predict both 180° (for (001)-/(101)-oriented films) and 90° multi-step switching (for (111)-oriented films) and these processes are subsequently observed in stroboscopic piezoresponse force microscopy. These results have implications for our understanding of ferroelectric switching and offer opportunities to change domain reversal speed.
Bibliographical noteFunding Information:
R.X. and S.L. acknowledge support from the National Science Foundation and the Nanoelectronics Research Initiative under grant DMR-1124696. I.G. acknowledges support from the US DOE under grant DE-FG02-07ER46431. J.K. acknowledges support from the National Science Foundation under grant DMR-1451219. A.R.D. and L.W.M. acknowledge support from the Army Research Office under grant W911NF-14-1-0104. A.M.R. acknowledges support from the Office of Naval Research under grant N00014-12-1-1033. The authors acknowledge computational support from the High-Performance Computing Modernization Office of the Department of Defense, and from the National Energy Research Scientific Computing Center of the Department of Energy.
© 2015 Macmillan Publishers Limited. © 2015 Macmillan Publishers Limited.