[1] [1] M. A. Nielsen and I. L. Chuang, Quantum Computation and Quantum Information (Cambridge University Press, Cambridge, 2000).

[2] [2] T. Yu and J. H. Eberly, Phys. Rev. Lett. 93, 140404(2004).

[3] [3] L. Jakobczyk and A. Jamroz, Phys. Lett. A 333, 35 (2004).

[4] [4] S. Bandyopadhyay and D. A. Lidar, Phys. Rev. A 70, 010301(R) (2004).

[5] [5] T. Yu and J. H. Eberly, Phys. Rev. Lett. 97, 140403 (2006).

[6] [6] P. J. Dodd and J. J. Halliwell, Phys. Rev. A 69, 052105 (2004).

[7] [7] M. Yona c, T. Yu, and J. H. Eberly, J. Phys. B: At. Mol. Opt. Phys. 40, S45 (2007).

[8] [8] D. Solenov, D. Tolkunov, and V. Privman, Phys. Lett. A 359, 81 (2006).

[9] [9] K. Zyczkowski, P. Horodecki, M. Horodecki, and R. Horodecki, Phys. Rev. A 65, 012101 (2001).

[10] [10] A. R. R. Carvalho, F. Mintert, and A. Buchleitner, Phys. Rev. Lett. 93, 230501 (2004).

[11] [11] L. Derkacz and L. Jakobczyk, Phys. Rev. A 74, 032313 (2006).

[12] [12] G. Gordon and G. Kurizki, Phys. Rev. Lett. 97, 110503 (2006).

[13] [13] M. P. Almeida, F. de Melo, M. Hor-Meyll, A. Salles, S. P. Walborn, P. H. S. Ribeiro, and L. Davidovich, Science 316, 579 (2007).

[14] [14] J. Laurat, K. S. Choi, H. Deng, C. W. Chou, and H. J. Kimble, Phys. Rev. Lett. 99, 180504 (2007).

[15] [15] W. Dur, G. Vidal, and J. I. Cirac, Phys. Rev. A 62, 062314 (2000).

[16] [16] N. B. An, Phys. Rev. A 69, 022315 (2004).

[17] [17] P. Agrawal and A. Pati, Phys. Rev. A 74, 062320 (2006).

[18] [18] V. Coffman, J. Kundu, and W. K. Wootters, Phys. Rev. A 61, 052306 (2000).

[19] [19] C. E. Lopez, G. Romero, F. Lastra, E. Solano, and J. C. Retamal, Phys. Rev. Lett. 101, 080503 (2008).

[20] [20] W. K. Wootters, Phys. Rev. Lett. 80, 2245 (1998).

[21] [21] G. Vidal and R. F. Werner, Phys. Rev. A 65, 032314 (2002).