Quantum Treatment of the Interaction Between an N-Level Atom and Two Noninteracting Two-Level Atoms

We consider the problem of two two-level atoms interacting with N-level atom. We obtain the exact solution for the wave function for the case where both atoms are identical and the system is treated at exact resonance. We use the results obtained for discussing the temporal evolution of the atomic inversion, in particular, the collapse and revival phenomena. We build up our discussion on the variation of the atomic number j and the atomic angle theta. For small j, the system exhibits a small period of collapse, and for large j we observe a long period of revival. We employ the linear entropy in the discussion of entanglement. We show that the atomic angle theta influences the system in such a way that the period of partial entanglement increases with increase in the value of theta. In addition to the variance squeezing, we also examine the entanglement between the spinors and show that the squeezing phenomenon occurs in the second quadrature, being absent in the first quadrature. Also we realize that the squeezing phenomenon reaches its maximum and gets more pronounced for a small value of the atomic number and a large value of the atomic angle.