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arXiv · 0801.2138

Weak Ferromagnetic Exchange and Anomalous Specific Heat in ZnCu3(OH)6Cl2

Ookie Ma·J. B. Marston
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Abstract

Experimental evidence for a plethora of low energy spin excitations in the spin-1/2 kagome antiferromagnet ZnCu3(OH)6Cl2 may be understandable in terms of an extended Fermi surface of spinons coupled to a U(1) gauge field. We carry out variational calculations to examine the possibility that such a state may be energetically viable. A Gutzwiller-projected wavefunction reproduces the dimerization of a kagome strip found previously by DMRG. Application to the full kagome lattice shows that the inclusion of a small ferromagnetic next-nearest-neighbor interaction favors a ground state with a spinon Fermi surface.

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Ookie Ma, J. B. Marston. 2008-01-28. Weak Ferromagnetic Exchange and Anomalous Specific Heat in ZnCu3(OH)6Cl2. https://doi.org/10.1103/physrevlett.101.027204

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