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Quantum numbers for relative ground states of antiferromagnetic Heisenberg spin rings

K. Baerwinkel·P. Hage·H. -J. Schmidt·J. Schnack
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Abstract

We suggest a general rule for the shift quantum numbers k of the relative ground states of antiferromagnetic Heisenberg spin rings. This rule generalizes well-known results of Marshall, Peierls, Lieb, Schultz, and Mattis for even rings. Our rule is confirmed by numerical investigations and rigorous proofs for special cases, including systems with a Haldane gap. Implications for the total spin quantum number S of relative ground states are discussed as well as generalizations to the XXZ model.

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BibTeXRIS

K. Baerwinkel, P. Hage, H. -J. Schmidt, J. Schnack. 2003-03-19. Quantum numbers for relative ground states of antiferromagnetic Heisenberg spin rings. https://doi.org/10.1103/physrevb.68.054422

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