The time evolution of populations of the λ type three-level atom with an additional Kerr medium was investigated theoretically. The influence of the single photon detuning between the field frequency and the atomic transition frequency, and the effect of the Kerr medium on the populations of the atom and the dynamic behaviour of the atom were analyzed respectively. Under the condition of X2n2≪2g2n, the populations of the atom show the collapse and revival phenomenon, and under the condition of X2...
