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One-dimensional Heisenberg antiferromagnet in which two S=1/2 and two S=1 spins are arranged alternatively

T. Tonegawa·T. Hikihara·T. Nishino·M. Kaburagi·S. Miyashita·H. -J. Mikeska
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Abstract

Ground-state and thermodynamic properties of the one-dimensional Heisenberg antiferromagnet in which two S=1/2 and two S=1 spins are arranged alternatively are studied by a quantum Monte Carlo method and by analytical estimates. It is found that the ground state of the system undergoes a second-order phase transition which accompanies the vanishing of the energy gap.

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T. Tonegawa, T. Hikihara, T. Nishino, M. Kaburagi, S. Miyashita, H. -J. Mikeska. 1997-12-26. One-dimensional Heisenberg antiferromagnet in which two S=1/2 and two S=1 spins are arranged alternatively. https://arxiv.org/abs/cond-mat/9712298

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