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arXiv · 0904.1287

Finite Temperature Properties of the Mixed Diamond Chain with Spins 1 and 1/2

Kazuo Hida·Ken'ichi Takano·Hidenori Suzuki
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Abstract

We formulate statistical mechanics for the mixed diamond chain with spins of magnitudes 1 and 1/2. Owing to a series of conservation laws, any eigenstate of this system is decomposed into eigenstates of finite odd-length spin-1 chains. The ground state undergoes five quantum phase transitions with varying the parameter $λ$ controlling frustration. We obtain the values of the residual entropy and the Curie constant which characterize each phase and phase boundary at low temperatures. We further find various characteristic finite-temperature properties such as the nonmonotonic temperature dependence of the magnetic susceptibility, the multipeak structure in the $λ$-dependence of entropy, the plateau-like temperature dependence of entropy and the multipeak structure of specific heat.

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Kazuo Hida, Ken'ichi Takano, Hidenori Suzuki. 2010-03-26. Finite Temperature Properties of the Mixed Diamond Chain with Spins 1 and 1/2. https://doi.org/10.1143/jpsj.78.084716

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