Experimental determination of superexchange energy from two-hole spectra

Giorgio Levy; Maayan Yaari; Tom Z. Regier; Amit Keren

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arXiv · 2107.09181

Experimental determination of superexchange energy from two-hole spectra

Giorgio Levy·Maayan Yaari·Tom Z. Regier·Amit Keren

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Abstract

We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (Ca$_{x}$La$_{1-x}$)(Ba$_{1.75-x}$La$_{0.25+x} $)Cu$_{3}$O$_{y}$ for $x=0.1$ and $x=0.4$. The spectra have contributions from band states as well as a localized multiplet structure. From their identification, we determine the intrashell Coulomb interaction $U$ for Oxygen and Copper sites. These results allow us to estimate the atomic superexchange coupling $J$ suggesting a positive correlation between the maximal superconducting critical temperature $T_\text{C}^{max}$ and $J$.

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Giorgio Levy, Maayan Yaari, Tom Z. Regier, Amit Keren. 2021-07-19. Experimental determination of superexchange energy from two-hole spectra. https://arxiv.org/abs/2107.09181

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