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arXiv · hep-th/9502051

Quantum chains with a Catalan tree pattern of conserved charges: the $Δ= -1$ XXZ model and the isotropic octonionic chain

M. P. Grabowski·P. Mathieu
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Abstract

A class of quantum chains possessing a family of local conserved charges with a Catalan tree pattern is studied. Recently, we have identified such a structure in the integrable $SU(N)$-invariant chains. In the present work we find sufficient conditions for the existence of a family of charges with this structure in terms of the underlying algebra. Two additional systems with a Catalan tree structure of conserved charges are found. One is the spin 1/2 XXZ model with $Δ=-1$. The other is a new octonionic isotropic chain, generalizing the Heisenberg model. This system provides an interesting example of an infinite family of noncommuting local conserved quantities.

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M. P. Grabowski, P. Mathieu. 1995-02-07. Quantum chains with a Catalan tree pattern of conserved charges: the $Δ= -1$ XXZ model and the isotropic octonionic chain. https://doi.org/10.1063/1.531266

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