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Low-temperature properties of the spin-1 antiferromagnetic Heisenberg chain with bond-alternation

Masanori Kohno·Minoru Takahashi·Masayuki Hagiwara
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Abstract

We investigate the low-temperature properties of the spin-1 antiferromagnetic Heisenberg chain with bond-alternation by the quantum Monte Carlo method (loop algorithm). The strength of bond-alternation at the gapless point is estimated as $δ_{c}=0.2595\pm0.0005$. We confirm numerically that the low-temperature properties at the gapless point are consistent with field theoretical predictions. The numerical results are compared with those of the spin-1/2 antiferromagnetic Heisenberg chain and recent experimental results for [\{Ni(333-tet)($μ$-N$_3$)\}$_n$](ClO$_4$)$_n$ (333-tet=tetraamine $N,N^{\prime}$-bis(3-aminopropyl)-1,3-propanediamine).

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Masanori Kohno, Minoru Takahashi, Masayuki Hagiwara. 1997-09-16. Low-temperature properties of the spin-1 antiferromagnetic Heisenberg chain with bond-alternation. https://doi.org/10.1103/physrevb.57.1046

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