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arXiv:cond-mat/9911327 · Physical review. B, Condensed matter

Exact ground state for one-dimensional electronic models

Д. В. Дмитриев, V. Ya. Krivnov, А. А. Овчинников

Published Jun 1, 2000• 8 citations
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Abstract

We have found the exact ground state for two electronic models on a linear chain. The first model describes a half-filling electron system at the ferromagnet-antiferromagnet transition point. In the singlet ground state the spin correlators show giant spiral magnetic ordering, with the period of a spiral equal to the system size. The second electronic model describes the point where the ground state has giant spiral off-diagonal long-range order and is, therefore, superconducting. We suggest the formation of a ground state with giant spiral order (ferromagnetic or off-diagonal) as a probable scenario of the subsequent destruction of the ferromagnetism and the superconductivity.

DOI
10.1103/physrevb.61.14592

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