DOI: 10.1142/S0217979211100126 International Journal of Modern Physics B Vol. 25, No. 8 (2011) 1091–1100 c  World Scientific Publishing Company DYNAMICS OF A THREE-LEVEL ATOM INTERACTING WITH A BIMODAL FIELD IN A RESONANT CAVITY ARPITA GHOSH * Physics and Applied Mathematics Unit, Indian Statistical Institute, 203, B.T. Road, Kolkata 700108, India * gh orpat@rediffmail.com Received 19 May 2009 Revised 11 August 2009 We have discussed the time evolution along with the nonclassicality phenomena of a system containing a vee-type three-level atom interacting with a bimodal electromagnetic field. A general expression for the atomic inversion is presented. It is found that the model undergoes Rabi oscillation. The total noise of the output state is measured. Keywords : Vee-type atom; nonclassicality; atomic inversion; noise. PACS number: 42.50.Ct 1. Introduction The time evolution of the state vector of a quantum system is fundamental to quantum optics as any experimental investigation of nonclassical features depends on the ability of creating and manipulating quantum states. In the context of cavity quantum electrodynamics (QED), methods have been presented to force a quantized electromagnetic field localized in a cavity from an initial ground state to any desired quantum state. 1,2 In these schemes the quantum state of one or more atoms are manipulated in a controllable way 3 and the coherence of the atom is transferred to the cavity field. The atoms act as the source, “teaching” the cavity field to evolve to the required state. The simplest model of quantum optics that gives a vivid description of the time evolution of the state vector is the exactly solvable Jaynes– Cummings model (JCM) consisting of a two-level atom coupled to a single quantized mode of the electromagnetic radiation field under the rotating-wave approximation. JCM yields various nonclassical results such as the collapses and revivals of the atomic inversion, 4 the squeezing of the field, 5 the atomic dipole 6 and the sub- Poissonian photon-counting statistics. 7 Later this model is generalized or extended in different directions. 8–10 For example, it is easily generalized to the case of a multilevel atom interacting with one or more discrete field modes. 11 Although three- level systems are very much popular and efficient systems for testing quantum 1091