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arXiv · 1009.1179

Spin Bose-Metal and Valence Bond Solid phases in a spin-1/2 model with ring exchanges on a four-leg triangular ladder

Matthew S. Block·D. N. Sheng·Olexei I. Motrunich·Matthew P. A. Fisher
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Abstract

We study a spin-1/2 system with Heisenberg plus ring exchanges on a four-leg triangular ladder using the density matrix renormalization group and Gutzwiller variational wave functions. Near an isotropic lattice regime, for moderate to large ring exchanges we find a spin Bose-metal phase with a spinon Fermi sea consisting of three partially filled bands. Going away from the triangular towards the square lattice regime, we find a staggered dimer phase with dimers in the transverse direction, while for small ring exchanges the system is in a featureless rung phase. We also discuss parent states and a possible phase diagram in two dimensions.

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Matthew S. Block, D. N. Sheng, Olexei I. Motrunich, Matthew P. A. Fisher. 2011-05-19. Spin Bose-Metal and Valence Bond Solid phases in a spin-1/2 model with ring exchanges on a four-leg triangular ladder. https://doi.org/10.1103/physrevlett.106.157202

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