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arXiv · 0910.2488

Visualizing elusive phase transitions with geometric entanglement

Roman Orus·Tzu-Chieh Wei
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Abstract

We show that by examining the global geometric entanglement it is possible to identify "elusive" or hard to detect quantum phase transitions. We analyze several one-dimensional quantum spin chains and demonstrate the existence of non-analyticities in the geometric entanglement, in particular across a Kosterlitz-Thouless transition and across a transition for a gapped deformed Affleck-Kennedy-Lieb-Tasaki chain. The observed non-analyticities can be understood and classified in connection to the nature of the transitions, and are in sharp contrast to the analytic behavior of all the two-body reduced density operators and their derived entanglement measures.

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Roman Orus, Tzu-Chieh Wei. 2010-10-01. Visualizing elusive phase transitions with geometric entanglement. https://doi.org/10.1103/physrevb.82.155120

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