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Marshall-Peierls sign rule for excited states of the frustrated J1-J2 Heisenberg antiferromagnet

A. Voigt·J. Richter·N. B. Ivanov
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Abstract

We present analytical and numerical calculations for some exited states of the frustrated J1-J2 spin-1/2 Heisenberg model for linear chains and square lattices. We consider the lowest eigenstates in the subspaces determined by the eigenvalue M of the spin operator S_total^z. Because of the reduced number of Ising basis states in the subspaces with higher M we are able to diagonalize systems with up to N=144 spins. We find evidence that the Marshall-Peierls sign rule survives for a relatively large frustration parameter J2.

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A. Voigt, J. Richter, N. B. Ivanov. 1997-05-31. Marshall-Peierls sign rule for excited states of the frustrated J1-J2 Heisenberg antiferromagnet. https://doi.org/10.1016/s0378-4371(97)00330-0

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