We analytically study the photon generation from vacuum due to the dynamical Casimir effect in a cavity with a two-level atom, initially prepared in an arbitrary pure state. Performing small unitary transformations, we obtain closed analytical expressions for the probability amplitudes and other important quantities in the resonant and dispersive regimes.

• Received 28 October 2011

DOI:https://doi.org/10.1103/PhysRevA.85.015805