Hierarchy of multiple many-body interaction scales in high-temperature superconductors

Abstract

To date, angle-resolved photoemission spectroscopy has been successful in identifying energy scales of the many-body interactions in correlated materials, focused on binding energies of up to a few hundred meV below the Fermi energy. Here, at higher-energy scale, we present improved experimental data from four families of high-${T}_{c}$ superconductors over a wide doping range that reveal a hierarchy of many-body interaction scales focused on: the low-energy anomaly (``kink'') of $0.03--0.09\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$, a high-energy anomaly of $0.3--0.5\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$, and an anomalous enhancement of the width of the local-density-approximation-based $\mathrm{Cu}{\mathrm{O}}_{2}$ band extending to energies of $\ensuremath{\approx}2\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$. Besides their universal behavior over the families, we find that all of these three dispersion anomalies also show clear doping dependence over the doping range presented.