Linear Entropy and Entanglement in Two-Charge-Qubit Circuits
LIAO Qing-Hong1, FANG Guang-Yu1, WANG Yue-Yuan1,2, AHMAD Muhammad Ashfaq3, LIU Shu-Tian1
1Department of Physics, Harbin Institute of Technology, Harbin 150001 2Key Laboratory for Advanced Functional Materials and Excited State Process of Heilongjiang Province, School of Physics and Electronic Engineering, Harbin Normal University, Harbin 150025 3Department of Physics, COMSATS Institute of Information Technology, Lahore 54000, Pakistan
Linear Entropy and Entanglement in Two-Charge-Qubit Circuits
LIAO Qing-Hong1, FANG Guang-Yu1, WANG Yue-Yuan1,2, AHMAD Muhammad Ashfaq3, LIU Shu-Tian1
1Department of Physics, Harbin Institute of Technology, Harbin 150001 2Key Laboratory for Advanced Functional Materials and Excited State Process of Heilongjiang Province, School of Physics and Electronic Engineering, Harbin Normal University, Harbin 150025 3Department of Physics, COMSATS Institute of Information Technology, Lahore 54000, Pakistan
We consider a model that contains two coupled superconducting charge qubits by sharing a large Josephson junction. We examine the dynamical properties of the linear entropy of two qubits and the probability of both qubits being in an excited state. The results show that the initial mean photon number, the initial phase of the field and the relative phase of the two qubits' levels play an important role in the evolution of the linear entropy of the two qubits and the probability.
We consider a model that contains two coupled superconducting charge qubits by sharing a large Josephson junction. We examine the dynamical properties of the linear entropy of two qubits and the probability of both qubits being in an excited state. The results show that the initial mean photon number, the initial phase of the field and the relative phase of the two qubits' levels play an important role in the evolution of the linear entropy of the two qubits and the probability.
LIAO Qing-Hong;FANG Guang-Yu;WANG Yue-Yuan;AHMAD Muhammad Ashfaq;LIU Shu-Tian. Linear Entropy and Entanglement in Two-Charge-Qubit Circuits[J]. 中国物理快报, 2010, 27(7): 70304-070304.
LIAO Qing-Hong, FANG Guang-Yu, WANG Yue-Yuan, AHMAD Muhammad Ashfaq, LIU Shu-Tian. Linear Entropy and Entanglement in Two-Charge-Qubit Circuits. Chin. Phys. Lett., 2010, 27(7): 70304-070304.
[1] Peres A 1993 Quantum Theory: Concepts and Methods (Dordrecht: Kluwer Academic) [2] Alber G, Beth T, Horodecki M, Horodecki P, Horodecki R, Rötteler M, Weinfurter W, Werner R and Zeilinger A 2001 Quantum Information: An Introduction to Basic Concepts and Experiments (Berlin: Springer) [3] Bennett C H, Brassard G, Crepeau C, Jozsa R, Peres A and Wootters W K 1993 Phys. Rev. Lett. 70 1895 [4] Bennett C H and Wiesner S J 1993 Phys. Rev. Lett. 69 2881 [5] Lieb E H and Seiringer R 2005 Phys. Rev. A 71 062309 [6] You J Q and Nori F 2003 Phys. Rev. B 68 064509 [7] Song K H 2009 Chin. Phys. Lett. 26 120302 [8] Kim M S, Lee J Y, Ahn D and Knight P L 2002 Phys. Rev. A 65 040101 [9] Wootters W K 1998 Phys. Rev. Lett. 80 2245 [10] Liu X N, Shao B and Zou J 2005 Chin. Phys. Lett. 22 2997 [11] Yang Q, Yang M and Cao Z L 2009 Chin. Phys. Lett. 26 040302 [12] Peres A 1996 Phys. Rev. Lett. 77 1413 [13] Vion D, Aasime A, Cottet A, Joyez P, Pothier H, Urbina C, Esteve D and Devoret M H 2002 Science 296 886 [14] Chiorescu I, Nakamura Y, Harmans C J P M and Mooij J E 2003 Science 299 1869 [15] Yu Y, Han S, Chu X, Chu S I and Wang Z 2002 Science 296 889 [16] Jaynes E T and Cummings F W 1963 Proc. IEEE 51 89 [17] Shore B W and Knight P L 1993 J. Mod. Opt. 40 1195 [18] He X L, Liu Y X, You J Q and Nori F 2007 Phys. Rev. A 76 022317 [19] El-Orany F A A 2007 Preprint quant-ph/07054373
2010, Vol. 27 
