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arXiv · 2411.17848

Singularity with and without disorder at AKLT points

Loïc Herviou·Anthony Rey·Frédéric Mila
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Abstract

The Affleck-Kennedy-Lieb-Tasaki (AKLT) point of the bilinear-biquadratic spin-1 chain is a cornerstone example of a disorder point where short-range correlations become incommensurate, and correlation lengths and momenta are non-analytic. While the presence of singularities appears to be generic for AKLT points, we show that for a family of SU(N) models, the AKLT point is not a disorder point: It occurs entirely within an incommensurate phase yet the wave vector remains singular on both sides of the AKLT point. We conjecture that this new possibility is generic for models where the representation is not self-conjugate and the transfer matrix non-Hermitian, while for self-conjugate representations the AKLT points remain disorder points.

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Loïc Herviou, Anthony Rey, Frédéric Mila. 2024-11-26. Singularity with and without disorder at AKLT points. https://arxiv.org/abs/2411.17848

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