Abstract This paper studies the interaction of a $\Lambda$-type three-level atom with a single mode field. It discusses the emission spectrum characteristics of the $\Lambda$-type three-level atom driven by the photon-added coherent field. By means of the second-order degree of coherence, it shows some nonclassical properties of the cavity field, such as sub-Poissonian photon-number distribution and the two-time intensity--intensity correlation which violates the Cauchy--Schwarz inequality.
Received: 22 November 2008
Revised: 23 January 2009
Accepted manuscript online:
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