Squeezing properties of the radiation field in the interaction of squeezed vacuum with two two-level atoms through two-photon transition

We study the squeezing and the amplitude-squared squeezing of radiation field in the interaction of squeezed vacuum state with two two-level atoms, and discuss the effects of the relative value of two atom-field coupling constants on them. The numerical results show that the presence of one additional atom introduces nontrivival cooperative effects into the squeezing and the amplitude-squared squeezing of radiation field.