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Connectivity transition in the frustrated S=1 chain revisited

A. K. Kolezhuk·U. Schollwoeck
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Abstract

The phase transition in the antiferromagnetic isotropic Heisenberg S=1 chain with frustrating next-nearest neighbor coupling alpha is reconsidered. We identify the order parameter of the large-alpha phase as describing two intertwined strings, each possessing a usual string order. The transition has a topological nature determined by the change in the string connectivity. Numerical evidence from the DMRG results is supported by the effective theory based on soliton states.

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A. K. Kolezhuk, U. Schollwoeck. 2001-10-04. Connectivity transition in the frustrated S=1 chain revisited. https://doi.org/10.1103/physrevb.65.100401

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