Document Type : Original Paper


1 Department of Physics, Faculty of Science , Shahid Chamran University of Ahvaz, Ahvaz, Iran

2 Department of Physics, Faculty of Science , Shahid Chamran University of Ahvaz, Iran


In this work, the entanglement of a superposition of bipartite qubit coherent states with non-phased coherent parameters is studied. We use Generalized-concurrence as the measure to quantify the entanglement and drive analytical results in terms of the effective parameters involved. Analyzing the results, we conclude that such states may attain maximum entanglement or no entanglement at all, depending on the choice of the parameters involved.


1. Bennett CH, Brassard G, Crepeau C, Jozsa R, Peres A,  Wootters WK.  Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels. Physical Review Letters. 1993;70(1895).
2. Terhal BM.  Detecting quantum entanglement. Theoretical Computer Science. 2002; 287: 313–335.
3. Horodecki R, Horodecki P, Horodecki M, Horodecki K. Quantum entanglement. Reviews of modern physics. 2009; 81(2): 865.
4.  Jaeger G. Quantum information.  Springer, New York, 2007.
 5. Sanders BC. Review of entangled coherent states. Journal of Physics A: Mathematical and Theoretical. 2012;45(24): 244002.
6.  Hollands S and Sanders K. Entanglement measures and their properties in quantum field theory. arXiv: quant-ph/1702.04924. 2017.
7. Prakash R. Use of entangled coherent states in quantum teleportation and entanglement diversion. Proceedings of the First International Workshop on ECS and Its Application to QIS; T.M.Q.C. 2013; 103-110.
8. Schaffry M, Gauger EM, Morton JJL, Fitzsimons J, Benjamin SC, Lovett BW. Quantum metrology with molecular ensembles. Physical Review A. 2010;82(4): 042114.
9.  Rungta P, Buzek V, Caves CM, Hillery M, Milburn GJ. Universal State Inversion and Concurrence in arbitrary Dimensions.Physical Review A. 2001; 64: 042315.
10. Rungta P, Caves CM. I-concurrence and Tangle for Isotropic States.  arXiv:  quant-ph/0208002v1. 2002.
11. Hill S, Wootters WK.  Entanglement of a Pair of Quantum Bits. Physical Review Letters. 1997;78: 5022.
12. Wootters WK. Entanglement of Formation of an Arbitrary State of Two Qubits. Physical Review Letters. 1998;80: 2245.
13.  Radcliffe JM. Some properties of coherent spin states.  Journal of Physics A. 1971; 4: 313.  
14. Berrada K, Chafik A, Eleuch H, Hassouni Y. Entanglement of Two-Qubit    Nonorthogonal States. International Journal of Modern Physics B.2009; 23:2021.
15. Jafarpour M, Ashrafpour M. An Entanglement Study of Superposition of   Qutrit Spin-Coherent States. Journal of Sciences, Islamic Republic of Iran.2011; 22(2): 165-169.