Absence of magnetic order for the spin-half Heisenberg antiferromagnet on the star lattice
Absence of magnetic order for the spin-half Heisenberg antiferromagnet on the star lattice
We study the ground-state properties of the spin-half Heisenberg antiferromagnet on the two-dimensional star lattice by spin-wave theory, exact diagonalization, and a variational mean-field approach. We find evidence that the star lattice is (besides the kagom\'e lattice) a second candidate among the 11 uniform Archimedean lattices where quantum fluctuations in …