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arXiv · 1909.06256

Tunable resistivity exponents in the metallic phase of epitaxial nickelates

Qikai Guo·Saeedeh Farokhipoor·César Magén·Francisco Rivadulla·Beatriz Noheda
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Abstract

We report a detailed analysis of the electrical resistivity exponent of thin films of NdNiO3 as a function of epitaxial strain. Strain-free thin-films show a linear dependence of the resistivity vs temperature, consistent with a classical Fermi gas ruled by electron-phonon interactions. In addition, the apparent temperature exponent, n, can be tuned with the epitaxial strain between n= 1 and n= 3. We discuss the critical role played by quenched random disorder in the value of n. Our work shows that the assignment of Fermi/Non-Fermi liquid behaviour based on experimentally obtained resistivity exponents requires an in-depth analysis of the degree of disorder in the material.

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Qikai Guo, Saeedeh Farokhipoor, César Magén, Francisco Rivadulla, Beatriz Noheda. 2019-09-13. Tunable resistivity exponents in the metallic phase of epitaxial nickelates. https://doi.org/10.1038/s41467-020-16740-5

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