Magnetization curves and low-temperature thermodynamics of two spin-1/2 Heisenberg edge-shared tetrahedra

A full energy spectrum, magnetization and susceptibility of a spin-1/2 Heisenberg model on two edge-shared tetrahedra are exactly calculated by assuming two different coupling constants. It is shown that a ground state in zero field is either a singlet or a triplet state depending on a relative stre...

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Bibliographic Details
Main Authors: Jozef Strečka, Katarína Karľová
Format: Article
Language:English
Published: AIP Publishing LLC 2018-10-01
Series:AIP Advances
Online Access:http://dx.doi.org/10.1063/1.5042029
Description
Summary:A full energy spectrum, magnetization and susceptibility of a spin-1/2 Heisenberg model on two edge-shared tetrahedra are exactly calculated by assuming two different coupling constants. It is shown that a ground state in zero field is either a singlet or a triplet state depending on a relative strength of both coupling constants. Low-temperature magnetization curves may exhibit three different sequences of intermediate plateaux at the following fractional values of the saturation magnetization: 1/3-2/3-1, 0-1/3-2/3-1 or 0-2/3-1. The inverse susceptibility displays a marked temperature dependence significantly influenced by a character of the zero-field ground state. The obtained theoretical results are confronted with recent high-field magnetization data of the mineral crystal fedotovite K2Cu3(SO4)3.
ISSN:2158-3226