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In the rotating-wave approximation,the produce and control for periodic quantum echo of atom bit interacting with a two-mode coherent light field is investigated via intensity-dependent coupling multiphoton channel by means of the full quantum theory.The effects on the evolution of the fidelity of atom bit for both the distribution form and distribution range of the average photon number of the two-mode coherent light field,and the photon number k of absorbed(emitted) as the atoms transition are discussed by numerical calculations,respectively.The system parameter of preparation and control for periodic quantum echo of atomic bits are obtained.According to the entanglement theory,the relation of the fidelity of atom bit with atomic reduced entropy is analyzed.The results show that atom bitkeeps good coherence and fidelity,and will produce periodic quantum echo for the two photon process as k=1,by regulation average photon number of the light fields being symmetrical or asymmetrical distribution and its value in a certain range.For k≥2 multiphoton process,the atom bit is always in a maximally entangled with the two-mode coherent light field so that the atom bit is in a state of partial distortion without periodic quantum echo.It is shown that the physical nature of the periodic quantum echo produce is periodic disentangled between the atom bit and the light field.