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arXiv · 1102.4414

Frustration-Induced Ferrimagnetism in S=1/2 Heisenberg Spin Chain

Tokuro Shimokawa·Hiroki Nakano
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Abstract

The ground-state properties of the S=1/2 frustrated Heisenberg spin chain with interactions up to fourth nearest neighbors are investigated by the exact-diagonalization method and density matrix renormalization group method. Our numerical calculations clarify that the ferrimagnetic state is realized in the ground state in spite of the fact that a multi-sublattice structure in the shape of the system is absent. We find that there are two types of ferrimagnetic phases: one is the well-known ferrimagnetic phase of the Lieb-Mattis type and the other is the nontrivial ferrimagnetic phase that is different from that of the Lieb-Mattis type. Our results suggest that a multi-sublattice structure of the shape is not necessarily required for the occurrence of ferrimagnetism.

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Tokuro Shimokawa, Hiroki Nakano. 2011-02-22. Frustration-Induced Ferrimagnetism in S=1/2 Heisenberg Spin Chain. https://doi.org/10.1143/jpsj.80.043703

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