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arXiv · 0811.1320

Exact spin-cluster ground states in a mixed diamond chain

Ken'ichi Takano·Hidenori Suzuki·Kazuo Hida
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Abstract

The mixed diamond chain is a frustrated Heisenberg chain composed of successive diamond-shaped units with two kinds of spins of magnitudes S and S/2 (S: integer). Ratio $lambda$ of two exchange parameters controls the strength of frustration. With varying $lambda$, the Haldane state and several spin cluster states appear as the ground state. A spin cluster state is a tensor product of exact local eigenstates of cluster spins. We prove that a spin cluster state is the ground state in a finite interval of $lambda$. For S=1, we numerically determine the total phase diagram consisting of five phases.

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Ken'ichi Takano, Hidenori Suzuki, Kazuo Hida. 2008-11-09. Exact spin-cluster ground states in a mixed diamond chain. https://doi.org/10.1103/physrevb.80.104410

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