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arXiv:0908.1281 · Physical Review B

Phase diagram of an anisotropic frustrated ferromagnetic spin- 12 chain in a magnetic field: A density matrix renormalization group study

Fabian Heidrich‐Meisner, Ian P. McCulloch, Alexei K. Kolezhuk

Published Oct 20, 2009• 71 citations
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Abstract

We study the phase diagram of a frustrated spin-$\frac{1}{2}$ ferromagnetic chain with anisotropic exchange interactions in an external magnetic field using the density matrix renormalization group method. We show that an easy-axis anisotropy enhances the tendency toward multimagnon bound states while an easy-plane anisotropy favors chirally ordered phases. In particular, a moderate easy-plane anisotropy gives rise to a quantum phase transition at intermediate magnetization. We argue that this transition is related to the finite-field phase transition experimentally observed in the spin-$\frac{1}{2}$ compound ${\text{LiCuVO}}_{4}$.

DOI
10.1103/physrevb.80.144417

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