Quantum trajectory theory for a two-level atom cascaded to a squeezed vacuum

The quantum trajectory theory is applied to a two-level atom cascaded to a squeezed vacuum. We use a model which holds for both broad bandwidth as well as narrow bandwidth squeezed vacua. The time evolution of single trajectories of the two-level atom reveals lesser quantum jumps with narrowing bandwidth of the squeezed vacuum, which in turn accounts for the smaller difference between the decay rates of the polarization quadratures of the atom.