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Role of random electric fields in relaxors.

ABSTRACT: PbZr(1-x)Ti(x)O3 (PZT) and Pb(Mg1/3Nb2/3)(1-x)Ti(x)O3 (PMN-xPT) are complex lead-oxide perovskites that display exceptional piezoelectric properties for pseudorhombohedral compositions near a tetragonal phase boundary. In PZT these compositions are ferroelectrics, but in PMN-xPT they are relaxors because the dielectric permittivity is frequency dependent and exhibits non-Arrhenius behavior. We show that the nanoscale structure unique to PMN-xPT and other lead-oxide perovskite relaxors is absent in PZT and correlates with a greater than 100% enhancement of the longitudinal piezoelectric coefficient in PMN-xPT relative to that in PZT. By comparing dielectric, structural, lattice dynamical, and piezoelectric measurements on PZT and PMN-xPT, two nearly identical compounds that represent weak and strong random electric field limits, we show that quenched (static) random fields establish the relaxor phase and identify the order parameter.

SUBMITTER: Phelan D

PROVIDER: S-EPMC3918832 | biostudies-other | 2014 Feb

REPOSITORIES: biostudies-other

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Role of random electric fields in relaxors.

Phelan Daniel D Stock Christopher C Rodriguez-Rivera Jose A JA Chi Songxue S Leão Juscelino J Long Xifa X Xie Yujuan Y Bokov Alexei A AA Ye Zuo-Guang ZG Ganesh Panchapakesan P Gehring Peter M PM

Proceedings of the National Academy of Sciences of the United States of America 20140121 5

PbZr(1-x)Ti(x)O3 (PZT) and Pb(Mg1/3Nb2/3)(1-x)Ti(x)O3 (PMN-xPT) are complex lead-oxide perovskites that display exceptional piezoelectric properties for pseudorhombohedral compositions near a tetragonal phase boundary. In PZT these compositions are ferroelectrics, but in PMN-xPT they are relaxors because the dielectric permittivity is frequency dependent and exhibits non-Arrhenius behavior. We show that the nanoscale structure unique to PMN-xPT and other lead-oxide perovskite relaxors is absent ...[more]

PMID: 24449912

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Role of random electric fields in relaxors.

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Role of random electric fields in relaxors.

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