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Properties of Pb(Zr,Ti)O$_3$ ultrathin films under stress-free and open-circuit electrical boundary conditions

Emad Almahmoud·Yulia Navtsenya·Igor Kornev·Huaxiang Fu·L. Bellaiche
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Abstract

A first-principles-based scheme is developed to simulate properties of (001) PbO-terminated Pb(Zr$_{1-x}$Ti$_{x}$)O$_3$ thin films that are under stress-free and open-circuit boundary conditions. Their low-temperature spontaneous polarization never vanishes down to the minimal thickness, and continuously rotates between the in-plane <010> and <110> directions when varying the Ti composition around x=0.50. Such rotation dramatically enhances piezoelectricity and dielectricity. Furthermore, the order of some phase transitions changes when going from bulk to thin films.

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Emad Almahmoud, Yulia Navtsenya, Igor Kornev, Huaxiang Fu, L. Bellaiche. 2004-10-29. Properties of Pb(Zr,Ti)O$_3$ ultrathin films under stress-free and open-circuit electrical boundary conditions. https://doi.org/10.1103/physrevb.70.220102

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