Abstract
We mainly discuss the calculations of non-classical fluorescence spectrum of electromagnetically induced transparency (EIT) in the thesis. EIT medium is an atomic system of Λ configuration consisted of three energy levels, interacted with two external incident EM waves propagating in the same direction, which are called probe and pump wave, respectively. By the quantum interference effect due to the pump wave, the probe wave can transmit the medium without being absorbed by the atoms inside medium, just as the medium is transparent. In general situation, the incident EM waves are ordinary coherent light (as laser light), and one mainly observe the fluorescence spectrum of probe wave. However, we consider a special case here: The incident probe wave is non-classical light (quantum squeezed state), and the pump wave is maintained an ordinary coherent light, and then we calculate the fluorescence spectrum of the two EM waves respectively. We utilize Mathematica program to solve the set of Heisenberg-Langevin equations corresponding to atom and EM fields. We find that the correlation between the quantum states of probe waves and pump wave are established. Their quantum properties mutually transfer, and the effect to be maxima when two fields approach equal intensities. This property presents that the quantum states of EM fields are changed, and completely different from initial quantum properties when propagating inside the EIT medium. Thus it implies that the EIT medium is not transparent for the quantum states of fields.