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arXiv:quant-ph/0604108 · Physical Review A

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

Xiao‐Feng Qian, Z. Song

Published Aug 2, 2006• 2 citations
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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 the counterpart system). A comparison of concurrence and mode concurrence can be made with the aid of 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 are discussed to demonstrate the analytical results.

DOI
10.1103/physreva.74.022302

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