Fidelities of quantum states in the system of the two-mode entangled coherent field interacting with atoms in Bell states in Kerr thin medium for fine cavity

Abstract

Abstract:

The fidelities of quantum states in the system of two-mode entangled coherent field interacting with two identical two-level atoms in the Bell state in Kerr thin medium are investigated by means of quantum theory and numerical method. The results indicate that for ideal cavity, the fidelity of the system always equals to one for the coherent maintenance state at original time when average photon number of two-mode entangled coherent states cavity fields are very small. When average photon number of two-mode entangled coherent states cavity fields increase, the fidelities of the system is humdrum attenuation. the fidelities of the system is nearer to one and Kerr medium more thin. The fidelities of the system surge periodically from 0 to 1 for the etceteras Bell state at original time when average photon number of two-mode entangled coherent states cavity fields are very small. When average photon number of two-mode entangled coherent states cavity fields increase, oscillatory frequency of the fidelities of the system augments and swing decrease. For fine cavity, the fidelity of the system is humdrum exponent attenuation for the coherent maintenance state at original time. The fidelities of the system are oscillatory exponent attenuation for the etceteras Bell state at original time, and when average photon number of two-mode entangled coherent states cavity fields increase, oscillatory frequency of the fidelities of the system augments and swing decrease.

Key words: quantum optics, fidelity, quantum theory, Bell states, Kerr thin medium, fine cavity

ZHANG Guoshun. Fidelities of quantum states in the system of the two-mode entangled coherent field interacting with atoms in Bell states in Kerr thin medium for fine cavity[J]. J4, 2010, 27(5): 586-595.

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