Journal of Applied Physics

Ground-state energy of spin-1/2 and spin-1 antiferromagnetic chains: X Y model

C. Y. Pan, H. Q. Lin

Published Nov 15, 1988• 1 citation

Abstract

The ground-state energy of the XY antiferromagnetic chains with spin-1/2 and spin-1 are obtained by a real space renormalization group method. For S=1/2 a large spin cluster is used in the mapping to improve the accuracy and a boundary theory is applied to extrapolate to the result which is in excellent agreement with the exact Bethe Ansatz result. For S=1 the ground-state energy of the model is obtained by using the renormalization group method and a finite chain calculation for lattices up to 16 sites. The two results are in very good agreement.

DOI: 10.1063/1.342179

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