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arXiv · 1712.09375

Integrability and duality in spin chains

Eyzo Stouten·Pieter W. Claeys·Jean-Sébastien Caux·Vladimir Gritsev
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Abstract

We construct a new, two-parametric family of integrable models and reveal their underlying duality symmetry. A modular subgroup of this duality is shown to connect non-interacting modes of different systems. We apply the new solution and duality to a Richardson-Gaudin model and generate a novel integrable system termed the $s$-$d$ wave Richardson-Gaudin-Kitaev interacting chain, interpolating $s$- and $d$- wave superconductivity. The phase diagram of this model has a topological phase transition that can be connected to the duality, where the occupancy of the non-interacting mode serves as a topological order parameter.

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Eyzo Stouten, Pieter W. Claeys, Jean-Sébastien Caux, Vladimir Gritsev. 2018-01-15. Integrability and duality in spin chains. https://doi.org/10.1103/physrevb.99.075111

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