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An efficient implementation of high-order coupled-cluster techniques applied to quantum magnets

Chen Zeng·D. J. J. Farnell·R. F. Bishop
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Abstract

We illustrate how the systematic inclusion of multi-spin correlations of the quantum spin-lattice systems can be efficiently implemented within the framework of the coupled-cluster method by examining the ground-state properties of both the square-lattice and the frustrated triangular-lattice quantum antiferromagnets. Various physical quantities including the ground-state energy, the anisotropy susceptibility, and the sublattice magnetisation are calculated and compared with those obtained from such other methods as series expansions and quantum Monte Carlo simulations.

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Chen Zeng, D. J. J. Farnell, R. F. Bishop. 1996-11-03. An efficient implementation of high-order coupled-cluster techniques applied to quantum magnets. https://doi.org/10.1023/a%3A1023220222019

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