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Interplane magnetic coupling effects in the multilattice compound Y_2Ba_4Cu_7O_{15}

G. Hildebrand·E. Arrigoni·J. Schmalian·W. Hanke
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Abstract

We investigate the interplane magnetic coupling of the multilattice compound Y_2Ba_4Cu_7O_{15} by means of a bilayer Hubbard model with inequivalent planes. We evaluate the spin response, effective interaction and the intra- and interplane spin-spin relaxation times within the fluctuation exchange approximation. We show that strong in-plane antiferromagnetic fluctuations are responsible for a magnetic coupling between the planes, which in turns leads to a tendency of the fluctuation in the two planes to equalize. This equalization effect grows whit increasing in-plane antiferromagnetic fluctuations, i. e., with decreasing temperature and decreasing doping, while it is completely absent when the in-layer correlation length becomes of the order of one lattice spacing. Our results provide a good qualitative description of NMR and NQR experiments in Y_2Ba_4Cu_7O_{15}.

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G. Hildebrand, E. Arrigoni, J. Schmalian, W. Hanke. 1998-12-07. Interplane magnetic coupling effects in the multilattice compound Y_2Ba_4Cu_7O_{15}. https://doi.org/10.1103/physrevb.59.r685

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