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arXiv · 1103.0441

Toroidal ferroelectricity in PbTiO3 nanoparticles

M. G. Stachiotti·M. Sepliarsky
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Abstract

We report from first-principles-based atomistic simulations that ferroelectricity can be sustained in PbTiO3 nanoparticles of only a few lattice constants in size as a result of a toroidal ordering. We found that size-induced topological transformations lead to the stabilization of a ferroelectric bubble by the alignment of vortex cores along a closed path. These transformations, which are driven by the aspect ratio of the nanostructure, change the topology of the polarization field, producing a rich variety of polar configurations. For sufficiently flat nanostructures, a multi-bubble state bridges the gap between 0D nanodots and 2D ultra-thin films. The thermal properties of the ferroelectric bubbles indicate that this state is suitable for the development of nanometric devices.

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M. G. Stachiotti, M. Sepliarsky. 2011-03-02. Toroidal ferroelectricity in PbTiO3 nanoparticles. https://doi.org/10.1103/physrevlett.106.137601

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