AI Article Synopsis
- The study focuses on the construction of PbTiO3/SrRuO3 superlattices with very thin SrRuO3 layers, revealing significant electrical resistivity differences depending on the layer thickness.
- By adjusting the PbTiO3 concentration, the team observed polarization asymmetry that breaks compositional inversion symmetry, which alters the electrical properties of the materials.
- The findings indicate a novel class of ferroelectric superlattices with complex behaviors arising from variations in both A and B site ions, supported by experimental data and theoretical modeling.
Article Abstract
We have fabricated PbTiO3/SrRuO3 superlattices with ultrathin SrRuO3 layers. Because of the superlattice geometry, the samples show a large anisotropy in their electrical resistivity, which can be controlled by changing the thickness of the PbTiO3 layers. Therefore, along the ferroelectric direction, SrRuO3 layers can act as dielectric, rather than metallic, elements. We show that, by reducing the concentration of PbTiO3, an increasingly important effect of polarization asymmetry due to compositional inversion symmetry breaking occurs. The results are significant as they represent a new class of ferroelectric superlattices, with a rich and complex phase diagram. By expanding our set of materials we are able to introduce new behaviors that can only occur when one of the materials is not a perovskite titanate. Here, compositional inversion symmetry breaking in bicolor superlattices, due to the combined variation of A and B site ions within the superlattice, is demonstrated using a combination of experimental measurements and first principles density functional theory.
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| http://dx.doi.org/10.1103/PhysRevLett.109.067601 | DOI Listing |
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