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Finite-lattice extrapolations for a Haldane gap antiferromagnet

O. Golinelli·Th. Jolicoeur·R. Lacaze
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Abstract

We present results of exact diagonalizations of the isotropic antiferromagnetic S=1 Heisenberg chain by the Lanczos method, for finite rings of up to N=22 sites. The Haldane gap G(N) and the ground state energy per site e(N) converge, with increasing N, faster than a power law. By VBS and Shanks transformations, the extrapolated values are G=0.41049(2) and e=-1.401485(2). The spin-spin correlation function is well fit by exp(-r/xi)/sqrt(r) with xi=6.2.

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O. Golinelli, Th. Jolicoeur, R. Lacaze. 1994-02-09. Finite-lattice extrapolations for a Haldane gap antiferromagnet. https://doi.org/10.1103/physrevb.50.3037

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