Abstract
We have investigated the evolution of the atomic quantum entropy and the entanglement of atom–photon in the system with competing k-photon and l-photon transitions by means of fully quantum theory, and examined the effects of competing photon numbers (k and l), the relative coupling strength between the atom and the two-mode field (λ/g), and the initial photon number of the field on the atomic quantum entropy and the entanglement of atom–photon. The results show that the multiphoton competing transitions or the large relative coupling strength can lead to the strong entanglement between atoms and photons. The maximal atom–photon entanglement can be prepared via the appropriate selection of system parameters and interaction time.