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arXiv · 1706.06370

Magnetization process and low-temperature thermodynamics of a spin-1/2 Heisenberg octahedral chain

Jozef Strecka·Johannes Richter·Oleg Derzhko·Taras Verkholyak·Katarina Karlova
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Abstract

Low-temperature magnetization curves and thermodynamics of a spin-1/2 Heisenberg octahedral chain with the intraplaquette and monomer-plaquette interactions are examined within a two-component lattice-gas model of hard-core monomers, which takes into account all low-lying energy modes in a highly frustrated parameter space involving the monomer-tetramer, localized many-magnon and fully polarized ground states. It is shown that the developed lattice-gas model satisfactorily describes all pronounced features of the low-temperature magnetization process and the magneto-thermodynamics such as abrupt changes of the isothermal magnetization curves, a double-peak structure of the specific heat or a giant magnetocaloric effect.

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Jozef Strecka, Johannes Richter, Oleg Derzhko, Taras Verkholyak, Katarina Karlova. 2017-06-20. Magnetization process and low-temperature thermodynamics of a spin-1/2 Heisenberg octahedral chain. https://doi.org/10.1016/j.physb.2017.09.118

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