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arXiv · 2308.06146

Stable dynamic helix state in the nonintegrable XXZ Heisenberg model

Gang Zhang·Zhi Song
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Abstract

We investigate the influence of external fields on the stability of spin helix states in an XXZ Heisenberg model. Exact diagonalization on a finite system shows that random transverse fields in the x and y directions drive the transition from integrability to nonintegrability. In such a system, the helix state can be regarded as a quantum scar. Simultaneously, the presence of uniform z field enables the helix state to better maintain its dynamical nature, allowing for a clearer understanding of its evolutionary behavior. However, the entanglement entropy reveals that irrespective of the presence of a uniform z field, as long as the system remains chaotic, the scar extent of the helix state shows no significant variation.

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Gang Zhang, Zhi Song. 2023-08-11. Stable dynamic helix state in the nonintegrable XXZ Heisenberg model. https://doi.org/10.1088/1402-4896%2Fad5886

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