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arXiv · 0804.4810

Phase diagram of the t-U-J1-J2 chain at half filling

X. Huang·E. Szirmai·F. Gebhard·J. Sólyom·R. M. Noack
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Abstract

We investigate the half-filled Hubbard chain with additional nearest- and next-nearest-neighbor spin exchange, J1 and J2, using bosonization and the density-matrix renormalization group. For J2 = 0 we find a spin-density-wave phase for all positive values of the Hubbard interaction U and the Heisenberg exchange J1. A frustrating spin exchange J2 induces a bond-order-wave phase. For some values of J1, J2 and U, we observe a spin-gapped metallic Luther-Emery phase.

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X. Huang, E. Szirmai, F. Gebhard, J. Sólyom, R. M. Noack. 2008-04-30. Phase diagram of the t-U-J1-J2 chain at half filling. https://doi.org/10.1103/physrevb.78.085128

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