The spin-1 / 2 Heisenberg antiferromagnet on a 1 / 7-depleted triangular lattice: Ground-state properties
D. Schmalfuβ1 , P. Tomczak2 , J. Schulenburg1 , J. Richter1
1 Institut für Theoretische Physik, Otto-von-Guericke Universität Magdeburg, P.O. Box 4120, 39016 Magdeburg, Germany
2 Department of Physics, A. Mickiewicz University, 61-614 Poznań, Poland
Physical Review B, 65, 224405 – 1-8 (2002)
A linear spin-wave approach, a variational method, and exact diagonalization are used to investigate the magnetic long-range order (LRO) of the spin-1 / 2 Heisenberg antiferromagnet on a two-dimensional 1 / 7-depleted triangular (maple leaf) lattice consisting of triangles and hexagons only. This lattice has z=5 nearest neighbors and its coordination number z is, therefore, between those of the triangular (z=6) and the kagomé (z=4) lattices. Calculating spin-spin correlations, sublattice magnetization, spin stiffness, spin-wave velocity and spin gap we find that the classical six-sublattice LRO, strongly renormalized by quantum fluctuations, however, also remains stable in the quantum model.