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arXiv · 2008.04336

QQ-system and Weyl-type transfer matrices in integrable SO(2r) spin chains

Gwenaël Ferrando·Rouven Frassek·Vladimir Kazakov
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Abstract

We propose the full system of Baxter Q-functions (QQ-system) for the integrable spin chains with the symmetry of the $D_r$ Lie algebra. We use this QQ-system to derive new Weyl-type formulas expressing transfer matrices in all symmetric and antisymmetric (fundamental) representations through $r+1$ basic Q-functions. Our functional relations are consistent with the Q-operators proposed recently by one of the authors and verified explicitly on the level of operators at small finite length.

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Gwenaël Ferrando, Rouven Frassek, Vladimir Kazakov. 2020-08-10. QQ-system and Weyl-type transfer matrices in integrable SO(2r) spin chains. https://doi.org/10.1007/jhep02(2021)193

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