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arXiv · 1609.09759

Influence of the ferroelectric quantum critical point on SrTiO$_3$ interfaces

W. A. Atkinson·P. Lafleur·A. Raslan
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Abstract

We study a model SrTiO$_3$ interface in which conduction $t_{2g}$ electrons couple to the ferroelectric (FE) phonon mode. We treat the FE mode within a self-consistent phonon theory that captures its quantum critical behavior, and show that proximity to the quantum critical point leads to universal tails in the electron density of the form $n(z) \sim (\lambda+z)^{-2}$, where $\lambda \sim T^{2-d/\mathfrak{z}}$, with $d=3$ the dimensionality and $\mathfrak{z}=1$ the dynamical critical exponent. Implications for the metal-insulator transition at low electron density are discussed.

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W. A. Atkinson, P. Lafleur, A. Raslan. 2016-09-30. Influence of the ferroelectric quantum critical point on SrTiO$_3$ interfaces. https://doi.org/10.1103/physrevb.95.054107

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