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arXiv · 1601.05319

Alternating-spin S=3/2 and sigma=1/2 Heisenberg chain with three-body exchange interactions

N. B. Ivanov·S. I. Petrova·J. Schnack
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Abstract

The promotion of collinear classical spin configurations as well as the enhanced tendency towards nearest-neighbor clustering of the quantum spins are typical features of the frustrating isotropic three-body exchange interactions in Heisenberg spin systems. Based on numerical density-matrix renormalization group calculations, we demonstrate that these extra interactions in the Heisenberg chain constructed from alternating S=3/2 and sigma=1/2 site spins can generate numerous specific quantum spin states, including some partially-polarized ferrimagnetic states as well as a doubly-degenerate non-magnetic gapped phase. In the non-magnetic region of the phase diagram, the model describes a crossover between the spin-1 and spin-2 Haldane-type states.

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N. B. Ivanov, S. I. Petrova, J. Schnack. 2016-01-20. Alternating-spin S=3/2 and sigma=1/2 Heisenberg chain with three-body exchange interactions. https://doi.org/10.1140/epjb%2Fe2016-70057-y

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