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arXiv · 1611.04301

Magnetization process and magnetocaloric effect of the spin-1/2 XXZ Heisenberg cuboctahedron

K. Karlova·J. Strecka
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Abstract

Magnetic properties of the spin-1/2 XXZ Heisenberg cuboctahedron are examined using exact numerical diagonalization depending on a relative strength of the exchange anisotropy. While the Ising cuboctahedron exhibits in a low-temperature magnetization curve only one-third magnetization plateau, the XXZ Heisenberg cuboctahedron displays another four intermediate plateaux at zero, one-sixth, one-half and two-thirds of the saturation magnetization. The novel magnetization plateaux generally extend over a wider range of magnetic fields with increasing of a quantum ($xy$) part of the XXZ exchange interaction. It is shown that the XXZ Heisenberg cuboctahedron exhibits in a vicinity of all magnetization jumps anomalous thermodynamic behavior accompanied with an enhanced magnetocaloric effect.

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K. Karlova, J. Strecka. 2016-11-14. Magnetization process and magnetocaloric effect of the spin-1/2 XXZ Heisenberg cuboctahedron. https://doi.org/10.1007/s10909-016-1676-8

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