Relaxor ferroelectrics
Relaxor ferroelectrics
Relaxors are site‐ and charge‐disordered crystals or solid solutions where charge disorder induces random fields. They are characterized by the appearance of polar nanoclusters that are much smaller than typical ferroelectric domains, and a broad distribution of relaxation times. The various physical properties of relaxors are discussed and the spherical random‐bond–random‐field model of these systems is also presented. As the various polar units in nanoclusters vary in orientation and size the system cannot be described by an ordering field of fixed length as in Ising systems. The order parameter field is thus continuous. The phase diagrams, neutron scattering, Raman spectra, heat conductivity and specific heat as well as the NMR lineshapes and relaxation times are discussed. The existence of electric‐field‐induced critical end points in the phase diagrams is demonstrated and discussed within the Landau theory.
Keywords: physical properties of relaxors, polar nanoclusters, distribution of relaxation times, random bonds, random fields, phase diagrams, critical end points, giant electromechanical effects
Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.
Please, subscribe or login to access full text content.
If you think you should have access to this title, please contact your librarian.
To troubleshoot, please check our FAQs , and if you can't find the answer there, please contact us .