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Recent progress in the truncated Lanczos method : application to hole-doped spin ladders

O. Chiappa·S. Capponi·D. Poilblanc
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Abstract

The truncated Lanczos method using a variational scheme based on Hilbert space reduction as well as a local basis change is re-examined. The energy is extrapolated as a power law function of the Hamiltonian variance. This systematic extrapolation procedure is tested quantitatively on the two-leg t-J ladder with two holes. For this purpose, we have carried out calculations of the spin gap and of the pair dispersion up to size 2x15.

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O. Chiappa, S. Capponi, D. Poilblanc. 2000-12-04. Recent progress in the truncated Lanczos method : application to hole-doped spin ladders. https://doi.org/10.1103/physrevb.63.115120

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