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arXiv · 2501.09477

From Complexification to Self-Similarity: New Aspects of Quantum Criticality

Yang Liu·Erhai Zhao·Haiyuan Zou
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Abstract

Quantum phase transitions are a fascinating area of condensed matter physics. The extension through complexification not only broadens the scope of this field but also offers a new framework for understanding criticality and its statistical implications. This mini review provides a concise overview of recent developments in complexification, primarily covering finite temperature and equilibrium quantum phase transitions, as well as their connection with dynamical quantum phase transitions and non-Hermitian physics, with a particular focus on the significance of Fisher zeros. Starting from the newly discovered self-similarity phenomenon associated with complex partition functions, we further discuss research on self-similar systems briefly. Finally, we offer a perspective on these aspects.

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Yang Liu, Erhai Zhao, Haiyuan Zou. 2025-01-16. From Complexification to Self-Similarity: New Aspects of Quantum Criticality. https://doi.org/10.1088/0256-307x%2F41%2F10%2F100501

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