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Exact diagonalization of the S=1/2 XY ferromagnet on finite bcc lattices to estimate T=0 properties on the infinite lattice

J. Schulenburg·J. S. Flynn·D. D. Betts·J. Richter
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Abstract

In this paper finite bcc lattices are defined by a triple of vectors in two different ways - upper triangular lattice form and compact form. In Appendix A are lists of some 260 distinct and useful bcc lattices of 9 to 32 vertices. The energy and magnetization of the S = 1/2 XY ferromagnet have been computed on these bcc lattices in the lowest states for $S_z$ = 0, 1/2, 1 and 3/2. These data are studied statistically to fit the first three terms of the appropriate finite lattice scaling equations. Our estimates of the T = 0 energy and magnetization agree very well with spin wave and series expansion estimates.

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J. Schulenburg, J. S. Flynn, D. D. Betts, J. Richter. 2001-05-15. Exact diagonalization of the S=1/2 XY ferromagnet on finite bcc lattices to estimate T=0 properties on the infinite lattice. https://doi.org/10.1007/s100510170195

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