title: Nanoscale mapping of heterogeneity of the polarization reversal in lead-free relaxor-ferroelectric ceramic composites.
abstract: Relaxor/ferroelectric ceramic/ceramic composites have shown to be promising in generating large electromechanical strain at moderate electric fields. Nonetheless, the mechanisms of polarization and strain coupling between grains of different nature in the composites remain unclear. To rationalize the coupling mechanisms we performed advanced piezoresponse force microscopy (PFM) studies of 0.92BNT-0.06BT-0.02KNN/0.93BNT-0.07BT (ergodic/non-ergodic relaxor) composites. PFM is able to distinguish grains of different phases by characteristic domain patterns. Polarization switching has been probed locally, on a sub-grain scale. k-Means clustering analysis applied to arrays of local hysteresis loops reveals variations of polarization switching characteristics between the ergodic and non-ergodic relaxor grains. We report a different set of switching parameters for grains in the composites as opposed to the pure phase samples. Our results confirm ceramic/ceramic composites to be a viable approach to tailor the piezoelectric properties and optimize the macroscopic electromechanical characteristics.
authors.affiliation: Institute for Material Science and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Essen 45141, Germany. vladimir.shvartsman@uni-due.de.
authors.forename: D
authors.initials: D
authors.lastname: Gobeljic
authors.affiliation: Institute for Material Science and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Essen 45141, Germany. vladimir.shvartsman@uni-due.de.
authors.forename: V V
authors.initials: VV
authors.lastname: Shvartsman
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
authors.forename: A
authors.initials: A
authors.lastname: Belianinov
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
authors.forename: B
authors.initials: B
authors.lastname: Okatan
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
authors.forename: S
authors.initials: S
authors.lastname: Jesse
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.
authors.forename: S V
authors.initials: SV
authors.lastname: Kalinin
authors.affiliation: Institute of Materials Science, Technische Universität Darmstadt, Darmstadt 64287, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Groh
authors.affiliation: Institute of Materials Science, Technische Universität Darmstadt, Darmstadt 64287, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Rödel
authors.affiliation: Institute for Material Science and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Essen 45141, Germany. vladimir.shvartsman@uni-due.de.
authors.forename: D C
authors.initials: DC
authors.lastname: Lupascu