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arXiv · 1411.7515

Frustrated diamond-chain quantum $XXZ$ Heisenberg antiferromagnet in a magnetic field

Johannes Richter·Olesia Krupnitska·Taras Krokhmalskii·Oleg Derzhko
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Abstract

We consider the antiferromagnetic spin-1/2 $XXZ$ Heisenberg model on a frustrated diamond-chain lattice in a $z$- or $x$-aligned external magnetic field. We use the strong-coupling approach to elaborate an effective description in the low-temperature strong-field regime. The obtained effective models are spin-1/2 $XY$ chains which are exactly solvable through the Jordan-Wigner fermionization. We perform exact-diagonalization studies of the magnetization curves to test the quality of the effective description. The results may have relevance for the description of the azurite spin-chain compound.

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Johannes Richter, Olesia Krupnitska, Taras Krokhmalskii, Oleg Derzhko. 2014-11-27. Frustrated diamond-chain quantum $XXZ$ Heisenberg antiferromagnet in a magnetic field. https://doi.org/10.1016/j.jmmm.2014.11.082

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