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Tetramerisation of a frustrated spin-1/2 chain

Federico Becca·Frederic Mila·Didier Poilblanc
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Abstract

We investigate a model of a frustrated spin-1/2 Heisenberg chain coupled to adiabatic phonons with a general form of magnetoelastic coupling. For large enough frustration and lattice coupling a new tetramerised phase with three different bond lengths is found. We argue that the zig-zag spin-1/2 chain LiV$_2$O$_5$ might be a good candidate to observe such a phase.

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Federico Becca, Frederic Mila, Didier Poilblanc. 2002-09-12. Tetramerisation of a frustrated spin-1/2 chain. https://doi.org/10.1103/physrevlett.91.067202

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