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The spin gap of CaV4O9 revisited

M. Mambrini·F. Mila
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Abstract

The large-plaquette scenario of the spin gap in CaV4O9 is investigated on the basis of extensive exact diagonalizations. We confirm the existence of a large-plaquette phase in a wide range of parameters, and we show that the most recent neutron scattering data actually require an intra-plaquette second neighbor exchange integral much larger than the inter-plaquette one, thus justifying the perturbative calculation used in the interpretation of the neutron scattering experiments.

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M. Mambrini, F. Mila. 1998-12-15. The spin gap of CaV4O9 revisited. https://doi.org/10.1016/s0921-4526(98)00726-1

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