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Spin-Orbital Entanglement and Phase Diagram of Spin-orbital Chain with $SU(2) \times SU(2)$ Symmetry

Yan Chen·Z. D. Wang·Y. Q. Li·F. C. Zhang
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Abstract

Spin-orbital entanglement in quantum spin-orbital systems is quantified by a reduced von Neumann entropy, and is calculated for the ground state of a coupled spin-orbital chain with $SU(2)\times SU(2)$ symmetry. By analyzing the discontinuity and local extreme of the reduced entropy as functions of the model parameters, we deduce a rich phase diagram to describe the quantum phase transitions in the model. Our approach provides an efficient and powerful method to identify phase boundaries in a system with complex correlation between multiply degrees of freedom.

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Yan Chen, Z. D. Wang, Y. Q. Li, F. C. Zhang. 2006-06-07. Spin-Orbital Entanglement and Phase Diagram of Spin-orbital Chain with $SU(2) \times SU(2)$ Symmetry. https://doi.org/10.1103/physrevb.75.195113

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