Variational calculation for the spin-(1/2 Heisenberg antiferromagnet on a square lattice

Dasgupta, Chandan (1989) Variational calculation for the spin-(1/2 Heisenberg antiferromagnet on a square lattice. In: Physical Review B: Condensed Matter, 39 (1). 386 -391.

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Abstract

The ground-state properties of the spin-(1/2 Heisenberg antiferromagnet on a square lattice are studied by using a simple variational wave function that interpolates continuously between the Néel state and short-range resonating-valence-bond states. Exact calculations of the variational energy for small systems show that the state with the lowest energy has long-range antiferromagnetic order. The staggered magnetization in this state is approximately 70% of its maximum possible value. The variational estimate of the ground-state energy is substantially lower than the value obtained for the nearest-neighbor resonating-valence-bond wave function.

Item Type:	Journal Article
Publication:	Physical Review B: Condensed Matter
Publisher:	The American Physical Society
Additional Information:	Copyright of this article belongs to The American Physical Society.
Department/Centre:	Division of Physical & Mathematical Sciences > Physics
Date Deposited:	20 Oct 2010 06:01
Last Modified:	20 Oct 2010 06:01
URI:	http://eprints.iisc.ac.in/id/eprint/33314

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