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arXiv · 0710.3457

Disordered ground states in a quantum frustrated spin chain with side chains

Ken'ichi Takano·Kazuo Hida
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Abstract

We study a frustrated mixed spin chain with side chains, where the spin species and the exchange interactions are spatially varied. A nonlinear sigma model method is formulated for this model, and a phase diagram with two disordered spin-gap phases is obtained for typical cases. Among them we examine the case with a main chain consisting of an alternating array of spin-1 and spin-1/2 sites and side chains each of a single spin-1/2 site in great detail. Based on numerical, perturbational, and variational approaches, we propose a singlet cluster solid picture for each phase, where the ground state is expressed as a tensor product of local singlet states.

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Ken'ichi Takano, Kazuo Hida. 2008-08-23. Disordered ground states in a quantum frustrated spin chain with side chains. https://doi.org/10.1103/physrevb.77.134412

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