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Planar Cu and O hole densities in high-Tc cuprates determined with NMR

J. Haase·O. P. Sushkov·P. Horsch·G. V. M. Williams
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Abstract

The electric hyperfine interaction observable in atomic spectroscopy for O and Cu ions in various configurations is used to analyze the quadrupole splitting of O and Cu nuclear magnetic resonance (NMR) in La2-xSrxCuO4 and YBa2Cu3O6+y and to determine the hole densities at both sites as a function of doping. It is found that in La2-xSrxCuO4 all doped holes (x) reside in the Cu-O plane but almost exclusively at O. For YBa2Cu3O6+y and y<0.6 doped holes are found at planar Cu as well as O. For y>0.6 further doping increases the hole content only for planar O. The phase diagram based on NMR data is presented. Further implications from the Cu A and B site in La2-xSrxCuO4 and the two planar O sites in YBa2Cu3O6+y and consequences for the phase diagram are discussed.

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J. Haase, O. P. Sushkov, P. Horsch, G. V. M. Williams. 2003-07-08. Planar Cu and O hole densities in high-Tc cuprates determined with NMR. https://doi.org/10.1103/physrevb.69.094504

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