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arXiv · 2312.10350

Continuous Phase Transition in Anyonic-PT Symmetric Systems

Zhihang Liu·Chao Zheng
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Abstract

We reveal the continuous phase transition in anyonic-PT symmetric systems, contrasting with the discontinuous phase transition corresponding to the discrete (anti-) PT symmetry. The continuous phase transition originates from the continuity of anyonic-PT symmetry. We find there are three information-dynamics patterns for anyonic-PT symmetric systems: damped oscillations with an overall decrease (increase) and asymptotically stable damped oscillations, which are three-fold degenerate and distorted using the Hermitian quantum R\'enyi entropy or distinguishability. It is the normalization of the non-unitary evolved density matrix causes the degeneracy and distortion. We give a justification for non-Hermitian quantum R\'enyi entropy being negative. By exploring the mathematics and physical meaning of the negative entropy in open quantum systems, we connect the negative non-Hermitian quantum R\'enyi entropy and negative quantum conditional entropy, opening up a new journey to rigorously investigate the negative entropy in open quantum systems.

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Zhihang Liu, Chao Zheng. 2023-12-16. Continuous Phase Transition in Anyonic-PT Symmetric Systems. https://arxiv.org/abs/2312.10350

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