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Relation between two measures of entanglement in spin-1/2 and spinless fermion quantum chain systems

Xiao-Feng Qian·Z. Song
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Abstract

The concepts of concurrence and mode concurrence are the measures of entanglement for spin-1/2 and spinless fermion systems respectively. Based on the Jordan-Wigner transformation, any spin-1/2 system is always associated with a fermion system (called counterpart system). The comparison of concurrence and mode concurrence can be made with the aid of the Marshall's sign rule for the ground states of spin-1/2 $XXZ$ and spinless fermion chain systems. We observe that there exists an inequality between concurrence and mode concurrence for the ground states of the two corresponding systems. The spin-1/2 XY chain system and its spinless fermion counterpart as a realistic example is discussed to demonstrate the analytical results.

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Xiao-Feng Qian, Z. Song. 2006-07-06. Relation between two measures of entanglement in spin-1/2 and spinless fermion quantum chain systems. https://doi.org/10.1103/physreva.74.022302

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