Abstract
The non-autonomous model of Bloch equations, modelling the coupling of a 2-photon 2-level single atom with a squeezed vacuum (SV) radiation reservoir, are treated via a Fourier Series (FS) decomposition approach. It is shown that both processes of quantum interference (QI), between the two indirect photon transition channels and the reservoir radiation squeezing, induce resonant zero absorption, accompanied by finite dispersion in the fundamental component and the 1st harmonic envelope component, which is associated with the positive frequency part of the atomic polarisation field. Negative absorption (amplification) can be seen with the corresponding envelope component of the negative frequency part.