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Numerical Analysis of the Bond-Random Antiferromagnetic S=1 Heisenberg Chain

Yoshihiro Nishiyama
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Abstract

Ground state of the bond-random antiferromagnetic S=1 Heisenberg chain with the biquadratic interaction -β\sum_i(S_i S_i+1)^2 is investigated by means of the exact-diagonalization method and the finite-size-scaling analysis. It is shown that the Haldane phase β\sim0 persists against the randomness; namely, no randomness-driven phase transition is observed until at a point of extremely-broad-bond distribution. We found that in the Haldane phase, the magnetic correlation length is kept hardly changed. These results are contrastive to those of an analytic theory which predicts a second-order phase transition between the Haldane and the random-singlet phases at a certain critical randomness.

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Yoshihiro Nishiyama. 1997-10-28. Numerical Analysis of the Bond-Random Antiferromagnetic S=1 Heisenberg Chain. https://doi.org/10.1016/s0378-4371(97)00616-x

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