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Three-spin interactions in optical lattices and criticality in cluster Hamiltonians

Jiannis K. Pachos·Martin B. Plenio
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Abstract

We demonstrate that in a triangular configuration of an optical lattice of two atomic species a variety of novel spin-1/2 Hamiltonians can be generated. They include effective three-spin interactions resulting from the possibility of atoms tunneling along two different paths. This motivates the study of ground state properties of various three-spin Hamiltonians in terms of their two-point and n-point correlations as well as the localizable entanglement. We present a Hamiltonian with a finite energy gap above its unique ground state for which the localizable entanglement length diverges for a wide interval of applied external fields, while at the same time the classical correlation length remains finite.

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Jiannis K. Pachos, Martin B. Plenio. 2004-04-13. Three-spin interactions in optical lattices and criticality in cluster Hamiltonians. https://doi.org/10.1103/physrevlett.93.056402

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