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KFM: Fachverband Kristalline Festkörper und deren Mikrostruktur
KFM 18: Materials Research in Polar Oxides: Perspectives for Optics & Electronics
KFM 18.6: Vortrag
Donnerstag, 20. März 2025, 17:15–17:30, H9
Piezoresponse force microscopy study of local polarization dynamics in uniaxial relaxors — •Vladimir Shvartsman1, Boris Slautin1, Jan Dec2, Sergei Kalinin3, and Doru Lupascu1 — 1Institute for Materials Science, University Duisburg-Essen, Essen, Germany — 2University of Silesia, Katowice, Poland — 3University of Tennessee-Knoxville, USA
The unusual properties of relaxor ferroelectrics are related to their particular polar structure. In these materials, the polarization is correlated only on the nanometer scale within the so called polar nanoregions (PNRs). The dynamics of PNRs strongly affects the dielectric properties of relaxors. Here, we report about piezoresponse force microscopy study of local polarization dynamics in SrxBa1-xNb2O6 single crystals. In these materials having uniaxial polarization, the cross-over from ferroelectric to relaxor behavior occurs with increasing Sr content making SBN a good model system. We use time-resolved piezoresponse force spectroscopy. This technique measures temporal decay of the piezoresponse induced by a locally applied electric field over a dense spatial grid. The analysis of the time dependences of the piezoresponse allows to estimate the local relaxation time. Spatial maps of relaxation parameters are constructed, giving information on the spatial heterogeneity of polarization dynamics for different compositions and temperatures. Temperature dependences of local relaxation time are analyzed.
Keywords: relaxor; stronrium barium niobate; piezoresponse force microscopy; polar nanoregions