Nonclassical states in cavity with injected atoms

It is found that displacement and squeezing of arbitrary initial states of the held can be produced in the model of a lossless cavity when a large num ber of two-level atoms is injected, which are prepared in a superposition s tate coupled to the single mode via a multi-photon transition under the wea k atom-field interaction. The dependence of the field density matrix elemen ts on the number of injected atoms indicates that due to the same initial a tomic coherence the emission of individual atoms is a co-operative process.