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Lattice instabilities of PbZrO3/PbTiO3 [1:1] superlattices from first principles

Claudia Bungaro·K. M. Rabe
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Abstract

Ab initio phonon calculations for the nonpolar reference structures of the (001), (110), and (111) PbZrO_3/PbTiO_3 [1:1] superlattices are presented. The unstable polar modes in the tetragonal (001) and (110) structures are confined in either the Ti- or the Zr-centered layers and display two-mode behavior, while in the cubic (111) case one-mode behavior is observed. Instabilities with pure oxygen character are observed in all three structures. The implications for the ferroelectric behavior and related properties are discussed.

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Claudia Bungaro, K. M. Rabe. 2002-01-31. Lattice instabilities of PbZrO3/PbTiO3 [1:1] superlattices from first principles. https://doi.org/10.1103/physrevb.65.224106

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