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arXiv · 2111.14455

Information diagrams in the study of entanglement in symmetric multi-quDit systems and applications to quantum phase transitions in Lipkin-Meshkov-Glick D-level atom models

Julio Guerrero·Alberto Mayorgas·Manuel Calixto
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Abstract

In this paper we pursue the use of information measures (in particular, information diagrams) for the study of entanglement in symmetric multi-quDit systems. We use generalizations to U(D) of spin U(2) coherent states and their adaptation to parity (multicomponent Schr\"odinger cats) and we analyse one- and two-quDit reduced density matrices. We use these correlation measures to characterize quantum phase transitions occurring in Lipkin-Meshkov-Glick models of D=3-level identical atoms and we propose the rank of the corresponding reduced density matrix as a discrete order parameter.

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Julio Guerrero, Alberto Mayorgas, Manuel Calixto. 2021-11-29. Information diagrams in the study of entanglement in symmetric multi-quDit systems and applications to quantum phase transitions in Lipkin-Meshkov-Glick D-level atom models. https://doi.org/10.1007/s11128-022-03524-7

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