An entanglement measure for n qubits

作者：Li Dafa^*; Li Xiangrong; Huang Hongtao; Li Xinxin

来源：Journal of Mathematical Physics, 2009, 50(1): 012104.

DOI：10.1063/1.3050298

• quantum computing
• quantum entanglement

Coffman [Phys. Rev. A 61, 052306 (2000)] introduced the residual entanglement for three qubits. In this paper, we present the entanglement measure tau(psi) for even n qubits; for odd n qubits, we propose the residual entanglement tau((i))(psi) with respect to qubit i and the odd n-tangle R(psi) by averaging the residual entanglement with respect to each qubit. In this paper, we show that these measures are LU-invariant, entanglement monotones, invariant under permutations of the qubits, and multiplicative in some cases.

• 出版日期2009-1
• 单位清华大学