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Linear energy bounds for Heisenberg spin systems

H. -J. Schmidt
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Abstract

Recently obtained results on linear energy bounds are generalized to arbitrary spin quantum numbers and coupling schemes. Thereby the class of so-called independent magnon states, for which the relative ground-state property can be rigorously established, is considerably enlarged. We still require that the matrix of exchange parameters has constant row sums, but this can be achieved by means of a suitable gauge and need not be considered as a physical restriction.

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H. -J. Schmidt. 2002-03-13. Linear energy bounds for Heisenberg spin systems. https://doi.org/10.1088/0305-4470%2F35%2F31%2F302

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