Journal of Weinan Normal University

STUDY on Evolution Properties of Fidelity of the Atomic Entangled State in the Union System

Wang Ju-xiaa

Published Jan 1, 2012• 0 citations

Abstract

The evolution process of atomic entangled state is discussed in the interaction of light-field with atoms by use of the complete quantum theory.The influence of multi-parameter on atomic fidelity is studied.Taking advantage of computation,the results show that atoms are always in partly entangled states during the process of interaction atoms with light fields.The evolution properties of fidelity of the atomic quantum state with time appear oscillatory and collapse-revert in a manner similar to Rabi oscillation.Its oscillatory frequency is mainly modulated by the radiation intensity or photon numbers,the coupling intensity between atoms and fight field,the complex probability amplitude of atoms jump,and the complex probability amplitude of annihilate a photon in the light field.And other factors hardly effect on the atomic fidelity.Hence,the entanglement degree and fidelity of atoms could be enhanced or weakened through controlling the three above parameters.

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