Entanglement of Fermi gases in a harmonic trap

  • X. X. YiEmail author
Quantum Optics and Quantum Information


For both cases with and without interactions, bipartite entanglement of two fermions from a Fermi gas in a trap is investigated. We show how the entanglement depends on the locations of the two fermions and the total particle number of the Fermi gas. Fermions at the edge of trap have longer entanglement distance (beyond it, the entanglement disappears) than those in the center. We derive a lower limitation to the average overlapping for two entangled fermions in the BCS ground state, it is shown to be \(\sqrt{Q/2M}\), a function of Cooper pair number Q and the total number of occupied energy levels M.


03.67.Mn Entanglement production, characterization, and manipulation 03.65.Ud Entanglement and quantum nonlocality 05.30.Fk Fermion systems and electron gas 74.20.Fg BCS theory and its development 


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© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2006

Authors and Affiliations

  1. 1.Department of physicsDalian University of TechnologyDalianP.R. China

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