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Projected wavefunction study of Spin-1/2 Heisenberg model on the Kagome lattice

Ying Ran·Michael Hermele·Patrick A. Lee·Xiao-Gang Wen
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Abstract

We perform a Gutzwiller projected wavefunction study for the spin-1/2 Heisenberg model on the Kagome lattice to compare energies of several spin-liquid states. The result indicates that a U(1)-Dirac spin-liquid state has the lowest energy. Furthermore, even without variational parameters, the energy turns out to be very close to that found by exact diagonalization. We show that such a U(1)-Dirac state represents a quantum phase whose low energy physics is governed by four flavors of two-component Dirac fermions coupled to a U(1) gauge field. These results are discussed in the context of recent experiments on ZnCu$_3$(OH)$_6$Cl$_2$.

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Ying Ran, Michael Hermele, Patrick A. Lee, Xiao-Gang Wen. 2006-11-15. Projected wavefunction study of Spin-1/2 Heisenberg model on the Kagome lattice. https://doi.org/10.1103/physrevlett.98.117205

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