Abstract
A dramatic influence of bias field on pyroelectric response was revealed for ceramics of (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 with x = 0.075, 0.33 and 0.98Pb(Fe1/2Nb1/2) O3–0.02PbTiO3. Temperature and bias field dependency of the dielectric permittivity and dynamic pyroelectric coefficient have been studied to establish possible relation of the enhanced pyroelectric activity with the E-T phase diagram. In relaxor ceramic composition PMN-0.075 the highest pyroelectric coefficient was achieved at the point having quasi-critical features. These data support an assumption of quasi-critical behavior of the pyroelectric response in relaxor ceramics, in accord with our previous data for relaxor single crystals.
Acknowledgments
This study was partly supported by the Russian Foundation for Basic Research (RFBR) grant 09-02-92672 IND_a and FTP (State contract P-487).