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Green's function theory of quasi-two-dimensional spin-half Heisenberg ferromagnets: stacked square versus stacked kagomé lattice

D. Schmalfuß·J. Richter·D. Ihle
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Abstract

We consider the thermodynamic properties of the quasi-two-dimensional spin-half Heisenberg ferromagnet on the stacked square and the stacked kagomé lattices by using the spin-rotation-invariant Green's function method. We calculate the critical temperature $T_C$, the uniform static susceptibility $χ$, the correlation lengths $ξ_ν$ and the magnetization $M$ and investigate the short-range order above $T_C$. We find that $T_C$ and $M$ at $T>0$ are smaller for the stacked kagomé lattice which we attribute to frustration effects becoming relevant at finite temperatures.

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D. Schmalfuß, J. Richter, D. Ihle. 2006-09-27. Green's function theory of quasi-two-dimensional spin-half Heisenberg ferromagnets: stacked square versus stacked kagomé lattice. https://doi.org/10.1103/physrevb.72.224405

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