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Tunable resistivity exponents in the metallic phase of epitaxial nickelates.

ABSTRACT: We report a detailed analysis of the electrical resistivity exponent of thin films of NdNiO₃ as a function of epitaxial strain. Thin films under low strain conditions show a linear dependence of the resistivity versus 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.

SUBMITTER: Guo Q

PROVIDER: S-EPMC7289814 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Tunable resistivity exponents in the metallic phase of epitaxial nickelates.

Guo Qikai Q Farokhipoor Saeedeh S Magén César C Rivadulla Francisco F Noheda Beatriz B

Nature communications 20200611 1

We report a detailed analysis of the electrical resistivity exponent of thin films of NdNiO<sub>3</sub> as a function of epitaxial strain. Thin films under low strain conditions show a linear dependence of the resistivity versus 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 ...[more]

PMID: 32527995

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