摘要
The bipartite entanglement in Fermi gas without interaction is investigated when there ace three fermions in the system. The negativity and the yon Neumann entropy are employed to measure the entanglement of the system. The position of the third fermion can affect the entanglement between the first and the second fermions. The entanglement can be enhanced or suppressed when the third fermion changes its position. When the two fermions are at the same position or when their distance is more than 2.0/kF, the third fermion cannot affect them.
基金
the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No.20050285002
National Natural Science Foundation of China under Grant No.10774108
