The Kagome Antiferromagnet: A Schwinger-Boson Mean-Field Theory Study

Abstract

The Heisenberg antiferromagnet on the Kagomé lattice is studied in the framework of Schwinger-boson mean-field theory. Two solutions with different symmetries are presented. One solution gives a conventional quantum state with $\mathbf{q}=0$ order for all spin values. Another gives a gapped spin liquid state for spin $S=1/2$ and a mixed state with both $\mathbf{q}=0$ and $\sqrt{3}\times \sqrt{3}$ orders for spin $S>1/2$. We emphasize that the mixed state exhibits two sets of peaks in the static spin structure factor. And for the case of spin $S=1/2$, the gap value we obtained is consistent with the previous numerical calculations by other means. We also discuss the thermodynamic quantities such as the specific heat and magnetic susceptibility at low temperatures and show that our result is in a good agreement with the Mermin-Wagner theorem.

9 pages, 5 figures

References in corpus (3)

• Spin Dynamics of the Spin-1/2 Kagome Lattice Antiferromagnet ZnCu_3(OH)_6Cl_2
• Projected wavefunction study of Spin-1/2 Heisenberg model on the Kagome lattice
• Spin Liquid States on the Triangular and Kagome Lattices: A Projective Symmetry Group Analysis of Schwinger Boson States

Cited by in corpus (4)

• Short-range magnetic ordering process for the triangular lattice compound NiGa2S4: a positive muon spin rotation and relaxation study
• Spontaneous dimerization and moment formation in the Hida model of spin-1 kagomé antiferromagnet
• Dynamical spin correlations in kagome antiferromagnets: comparison of Abrikosov fermion and Schwinger boson approaches beyond mean field
• Schwinger boson theory for $S=1$ Kitaev quantum spin liquids