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Green's function approach to the magnetic properties of the kagome antiferromagnet

B. H. Bernhard·B. Canals·C. Lacroix
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Abstract

The $S=1/2$ Heisenberg antiferromagnet is studied on the kagomé lattice by using a Green's function method based on an appropriate decoupling of the equations of motion. Thermodynamic properties as well as spin-spin correlation functions are obtained and characterize this system as a two-dimensional quantum spin liquid. Spin-spin correlation functions decay exponentially with distance down to low temperature and the calculated missing entropy at T=0 is found to be $0.46\ln{2}$. Within the present scheme, the specific heat exhibits a single peak structure and a $T^2$ dependence at low temperature.

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B. H. Bernhard, B. Canals, C. Lacroix. 2002-02-15. Green's function approach to the magnetic properties of the kagome antiferromagnet. https://doi.org/10.1103/physrevb.66.104424

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