Edge effects in the two-dimensional spin-1/2 Heisenberg antiferromagnet

Abstract

We use quantum Monte Carlo simulations to study effects of free edges in the two-dimensional spin-1/2 Heisenberg antiferromagnet. We find that the magnetic response of an edge is smaller than the bulk susceptibility. This counter-intuitive quantum effect can be traced to enhanced antiferromagnetic nearest-neighbor spin correlations, i.e., tendency to local singlet formation, at and close to the edge. These correlations form a comb-like pattern, which can be reproduced with a simple variational valence-bond state. We also study rough edges, and find that these instead significantly enhance the susceptibility, due to local sublattice imbalance impeding singlet formation.

4 pages, 5 figures

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Cited by in corpus (10)

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• Generalization of the singlet sector valence bond loop algorithm to antiferromagnetic ground states with total spin $S_{tot}=1/2$
• Spin correlations near the edge as probe of Dimer order in square-lattice Heisenberg models
• Spin wave calculation of the field-dependent magnetization pattern around an impurity in Heisenberg antiferromagnets
• Spin correlations near the surface of a three-dimensional Heisenberg antiferromagnet
• Effects of edge disorder in nano-scale antiferromagnetic clusters
• Near-Boundary and Bulk Regions of a Semi-Infinite Two-Dimensional Heisenberg Antiferromagnet
• Excitations and spin correlations near the interface of two three-dimensional Heisenberg antiferromagnets
• The t-J model on a semi-infinite lattice