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arXiv · 1902.05512

Charge transport in oxygen-deficient EuTiO$_3$: the emerging picture of dilute metallicity in quantum-paraelectric perovskite oxides

Johannes Engelmayer·Xiao Lin·Christoph P. Grams·Raphael German·Tobias Fröhlich·Joachim Hemberger·Kamran Behnia·Thomas Lorenz
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Abstract

We report on a study of charge transport in EuTiO$_{3-\delta}$ single crystals with carrier density tuned across several orders of magnitude. Comparing this system with other quasi-cubic perovskites, in particular strontium titanate, we draw a comprehensive picture of metal-insulator transition and dilute metallicity in this $AB$O$_3$ family. Because of a lower electric permittivity, the metal-insulator transition in EuTiO$_{3-\delta}$ occurs at higher carrier densities compared to SrTiO$_3$. At low temperature, a distinct $T^2$ resistivity is visible. Its prefactor $A$ smoothly decreases with increasing carrier concentration in a similar manner in three different perovskites. Our results draw a comprehensive picture of charge transport in doped quantum paraelectrics.

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Johannes Engelmayer, Xiao Lin, Christoph P. Grams, Raphael German, Tobias Fröhlich, Joachim Hemberger, Kamran Behnia, Thomas Lorenz. 2019-02-14. Charge transport in oxygen-deficient EuTiO$_3$: the emerging picture of dilute metallicity in quantum-paraelectric perovskite oxides. https://doi.org/10.1103/physrevmaterials.3.051401

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