arXiv:cond-mat/0409083 · Physical Review E
Soluble kagome Ising model in a magnetic field
Wentao Lu, Fa Yueh Wu
Abstract
An Ising model on the kagome lattice with super-exchange interactions is solved exactly under the presence of a nonzero external magnetic field. The model generalizes the super-exchange model introduced by Fisher in 1960 and is analyzed in light of a free-fermion model. We deduce the critical condition and present detailed analyses of its thermodynamic and magnetic properties. The system is found to exhibit a second-order transition with logarithmic singularities at criticality.