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arXiv · 1102.1001

Ground-state structure of KNbO$_3$/KTaO$_3$ superlattices: Array of nearly independent ferroelectrically ordered planes

Alexander I. Lebedev
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Abstract

Phonon spectra of the paraelectric phase, structure and distribution of polarization in the polar ground state, and energies of ferroelectrically and antiferroelectrically ordered phases were calculated for stress-free (KNbO$_3$)$_1$(KTaO$_3$)$_n$ superlattices ($n = {}$1--7) from first principles within the density-functional theory. Quasi-two-dimensional ferroelectric state with the polarization localized in the KNbO$_3$ layer was revealed to be the ground state for the superlattices with $n \ge 2$. The interaction between these polarized layers decreases exponentially with increasing the interlayer distance, and the ground-state structure transforms to an array of nearly independent ferroelectrically ordered planes at large $n$.

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Alexander I. Lebedev. 2012-04-17. Ground-state structure of KNbO$_3$/KTaO$_3$ superlattices: Array of nearly independent ferroelectrically ordered planes. https://doi.org/10.1002/pssb.201147350

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