Suppressed dependence of polarization on epitaxial strain in highly polar ferroelectrics.

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Phys. Rev. Lett.

DOI:https://doi.org/10.1103/PhysRevLett.98.217602· OSTI ID:953806

Lee, H N; Nakhmanson, S M; Chisholm, M F; Christen, H M; Rabe, K M; Vanderbilt, D; ORNL,

A combined experimental and computational investigation of coupling between polarization and epitaxial strain in highly polar ferroelectric PbZr{sub 0.2}Ti{sub 0.8}O{sub 3} (PZT) thin films is reported. A comparison of the properties of relaxed (tetragonality c/a{approx}1.05) and highly strained (c/a{approx}1.09) epitaxial films shows that polarization, while being amongst the highest reported for PZT or PbTiO{sub 3} in either film or bulk forms (P{sub r}{approx}82 {mu}C/cm{sup 2}), is almost independent of the epitaxial strain. We attribute this behavior to a suppressed sensitivity of the A-site cations to epitaxial strain in these Pb-based perovskites, where the ferroelectric displacements are already large, contrary to the case of less polar perovskites, such as BaTiO{sub 3}. In the latter case, the A-site cation (Ba) and equatorial oxygen displacements can lead to substantial polarization increases.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 953806
• Report Number(s): ANL/MSD/JA-59216
• Journal Information: Phys. Rev. Lett., Journal Name: Phys. Rev. Lett. Journal Issue: 2007 Vol. 98; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

36 MATERIALS SCIENCE
CATIONS
COUPLING
EPITAXY
FERROELECTRIC MATERIALS
OXYGEN
PEROVSKITES
POLARIZATION
PZT
SENSITIVITY
STRAINS
THIN FILMS