Ferroelectric properties of KnbO{sub 3}/KTaO{sub 3} superlattices by atomic-level simulation.

Journal Article · Thu Nov 01 04:00:00 EST 2001 · J. Appl. Phys.

DOI:https://doi.org/10.1063/1.1410329· OSTI ID:949316

Sepliarsky, M; Phillpot, S R; Wolf, D; Stachiotti, M G; Migoni, R L; UNR, CONICET -

We use atomic-level simulation methods to determine the zero-temperature structure and properties of coherent KNbO{sub 3}/KTaO{sub 3} superlattices. We find that the in-plane behavior is essentially bulk-like with an abrupt jump in the polarization at the interfaces. By contrast, the polarization in the modulation direction is continuous through the interfaces with the interior of the KTaO{sub 3} layers remaining polarized for modulation lengths of up to 160 unit cells. The zero-frequency dielectric constant in the modulation direction has a similar magnitude to that of KNbO{sub 3}. An investigation of the switching behavior shows that for modulation lengths greater than 24 unit cells, each KNbO{sub 3} layer behaves essentially independently. For modulation lengths of less than 12 unit cells, the KNbO{sub 3} layers interact so strongly with each other that the superlattice essentially behaves as a single artificial structure.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC; FOR
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 949316
• Report Number(s): ANL/MSD/JA-39893
• Journal Information: J. Appl. Phys., Journal Name: J. Appl. Phys. Journal Issue: 9 ; Nov. 1, 2001 Vol. 90; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

99 GENERAL AND MISCELLANEOUS
FERROELECTRIC MATERIALS
MODULATION
PERMITTIVITY
POLARIZATION
SIMULATION
SUPERLATTICES