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Series expansion analysis of a tetrahedral cluster spin chain

Marcelo Arlego·Wolfram Brenig
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Abstract

Using series expansion by continuous unitary transformations we study the magnetic properties of a frustrated tetrahedral spin-1/2 chain. Starting from the limit of isolated tetrahedra we analyze the evolution of the ground state energy and the elementary triplet dispersion as a function of the inter-tetrahedral coupling. The quantum phase diagram is evaluated and is shown to incorporate a singlet product, a dimer, and a Haldane phase. Comparison of our results with those from several other techniques, such as density matrix renormalization group, exact diagonalization and bond-operator theory are provided and convincing agreement is found.

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Marcelo Arlego, Wolfram Brenig. 2005-09-14. Series expansion analysis of a tetrahedral cluster spin chain. https://doi.org/10.1140/epjb%2Fe2006-00366-7

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