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Magnetism of a tetrahedral cluster spin-chain

Wolfram Brenig·Klaus W. Becker
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Abstract

We discuss the magnetic properties of a dimerized and completely frustrated tetrahedral spin-1/2 chain. Using a combination of exact diagonalization and bond-operator theory the quantum phase diagram is shown to incorporate a singlet-product, a dimer, and a Haldane phase. In addition we consider one-, and two-triplet excitations in the dimer phase and evaluate the magnetic Raman cross section which is found to be strongly renormalized by the presence of a two-triplet bound state. The link to a novel tellurate materials is clarified.

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Wolfram Brenig, Klaus W. Becker. 2001-05-04. Magnetism of a tetrahedral cluster spin-chain. https://doi.org/10.1103/physrevb.64.214413

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