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Phase Diagram of a Spin Ladder with Cyclic Four Spin Exchange

A. Laeuchli·G. Schmid·M. Troyer
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Abstract

We present the phase diagram of the $S=1/2$ Heisenberg model on the two leg ladder with cyclic four spin exchange, determined by a combination of Exact Diagonalization and Density Matrix Renormalization Group techniques. We find six different phases and regimes: the rung singlet phase, a ferromagnetic phase, two symmetry broken phases with staggered dimers and staggered scalar chiralities, and a gapped region with dominant vector chirality or collinear spin correlations. We localize the phase transitions and investigate their nature.

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A. Laeuchli, G. Schmid, M. Troyer. 2003-04-11. Phase Diagram of a Spin Ladder with Cyclic Four Spin Exchange. https://doi.org/10.1103/physrevb.67.100409

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