Propagation of squeezed vacuum under electromagnetically induced transparency

We analyze the transmission of continuous-wave and pulsed squeezed vacuum through rubidium vapor under the conditions of electromagnetically induced transparency. Our analysis is based on a full theoretical treatment for a squeezed state of light propagating through temporal and spectral filters and detected using time and frequency-domain homodyne tomography. A model based on a three-level atom allows us to evaluate the linear losses and extra noise that degrade the nonclassical properties of the squeezed vacuum during the atomic interaction and eventually predict the quantum states of the transmitted light with a high precision.