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Role of strong correlation in the recent ARPES experiments for cuprate superconductors

S. Yunoki·E. Dagotto·S. Sorella
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Abstract

Motivated by recent photoemission experiments on cuprates, the low-lying excitations of a strongly correlated superconducting state are studied numerically. It is observed that along the nodal direction these low-lying one-particle excitations show a linear momentum dependence for a wide range of excitation energies and, thus, they do not present a kink-like structure. The nodal Fermi velocity $v_{\rm F}$, as well as other observables, are systematically evaluated directly from the calculated dispersions, and they are found to compare well with experiments. It is argued that the parameter dependence of $v_{\rm F}$ is quantitatively explained by a simple picture of a renormalized Fermi velocity.

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S. Yunoki, E. Dagotto, S. Sorella. 2004-12-16. Role of strong correlation in the recent ARPES experiments for cuprate superconductors. https://doi.org/10.1103/physrevlett.94.037001

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