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arXiv · 1106.3846

Effects of Single-site Anisotropy on Mixed Diamond Chains with Spins 1 and 1/2

Kazuo Hida·Ken'ichi Takano
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Abstract

Effects of single-site anisotropy on mixed diamond chains with spins 1 and 1/2 are investigated in the ground states and at finite temperatures. There are phases where the ground state is a spin cluster solid, i.e., an array of uncorrelated spin-1 clusters separated by singlet dimers. The ground state is nonmagnetic for the easy-plane anisotropy, while it is paramagnetic for the easy-axis anisotropy. Also, there are the Néel, Haldane, and large-$D$ phases, where the ground state is a single spin cluster of infinite size and the system is equivalent to the spin-1 Heisenberg chain with alternating anisotropy. The longitudinal and transverse susceptibilities and entropy are calculated at finite temperatures in the spin-cluster-solid phases. Their low-temperature behaviors are sensitive to anisotropy.

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Kazuo Hida, Ken'ichi Takano. 2011-09-27. Effects of Single-site Anisotropy on Mixed Diamond Chains with Spins 1 and 1/2. https://doi.org/10.1143/jpsj.80.104710

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