arXiv:cond-mat/0111424 · Journal of Physics Condensed Matter

The study of spin-spin correlations in quasi-one-dimensional Heisenberg antiferromagnetic clusters

Yong-Jun Liu, Chang-De Gong

Published Dec 24, 2001• 7 citations

Abstract

For a class of quasi-one-dimensional clusters, by using exact diagonalization, we study the effect of side spins on the spin-spin correlations on chain. Our calculations show that the side spins added in the same sublattice can effectively strengthen the spin-spin correlations in large distance region and make the change tend to flat. It is exactly proved that periodically adding side spins can set up magnetic long-range orders in the ground state. Also we investigate the effect of the density of side spins on correlation strength. The case that two sublattices have different localized spins is discussed.

DOI: 10.1088/0953-8984/14/3/317

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arXiv:cond-mat/0111424 · Journal of Physics Condensed Matter

The study of spin-spin correlations in quasi-one-dimensional Heisenberg antiferromagnetic clusters

Yong-Jun Liu, Chang-De Gong

Published Dec 24, 2001• 7 citations

arXiv HTML PDF

Abstract

DOI: 10.1088/0953-8984/14/3/317

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{)}^{\mathit{r}}

c/${\mathit{r}}^{\mathrm{\ensuremath{\eta}}}$-

{\mathit{c}}_{1}

{\mathit{r}}^{2}

for large distance r. The power \ensuremath{\eta} depends on the Ising anisotropy, and \ensuremath{\eta}=0.405 at XY point and \ensuremath{\eta}=1.062 at Heisenberg point. For the two-dimensional square lattice, there is long-range staggered magnetization, and the dependence of magnetization on Ising anisotropy is given. For the crossover from one-dimensional linear chain to two-dimensional square lattice, we find that the disorder-order transition occurs as long as the interchain coupling is introduced. We believe that our method gives a unified approach to the long-range behavior of spin correlations in low-dimensional spin-1/2 antiferromagnets.