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Quantitative assessment of the universal thermopower in the Hubbard model.

ABSTRACT: As primarily an electronic observable, the room-temperature thermopower S in cuprates provides possibilities for a quantitative assessment of the Hubbard model. Using determinant quantum Monte Carlo, we demonstrate agreement between Hubbard model calculations and experimentally measured room-temperature S across multiple cuprate families, both qualitatively in terms of the doping dependence and quantitatively in terms of magnitude. We observe an upturn in S with decreasing temperatures, which possesses a slope comparable to that observed experimentally in cuprates. From our calculations, the doping at which S changes sign occurs in close proximity to a vanishing temperature dependence of the chemical potential at fixed density. Our results emphasize the importance of interaction effects in the systematic assessment of the thermopower S in cuprates.

SUBMITTER: Wang WO

PROVIDER: S-EPMC10624669 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Quantitative assessment of the universal thermopower in the Hubbard model.

Wang Wen O WO Ding Jixun K JK Huang Edwin W EW Moritz Brian B Devereaux Thomas P TP

Nature communications 20231103 1

As primarily an electronic observable, the room-temperature thermopower S in cuprates provides possibilities for a quantitative assessment of the Hubbard model. Using determinant quantum Monte Carlo, we demonstrate agreement between Hubbard model calculations and experimentally measured room-temperature S across multiple cuprate families, both qualitatively in terms of the doping dependence and quantitatively in terms of magnitude. We observe an upturn in S with decreasing temperatures, which po ...[more]

PMID: 37923746

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