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arXiv · 0901.2019

Exploring frustrated spin-systems using Projected Entangled Pair States (PEPS)

V. Murg·F. Verstraete·J. I. Cirac
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Abstract

We study the nature of the ground state of the frustrated J1-J2 model and the J1-J3 model using a variational algorithm based on projected entangled-pair states (PEPS). By investigating spin-spin correlation functions, we observe a separation in regions with long-range and short-range order. A direct comparison with exact diagonalizations in the subspace of short-range valence bond singlets reveals that the system is well described by states within this subset in the short-range order regions. We discuss the question whether the system forms a spin-liquid, a plaquette valence bond crystal or a columnar dimer crystal in these regions.

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V. Murg, F. Verstraete, J. I. Cirac. 2009-01-14. Exploring frustrated spin-systems using Projected Entangled Pair States (PEPS). https://doi.org/10.1103/physrevb.79.195119

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