Absorption and dispersion in a medium with electromagnetically induced interference

Amitabh Joshi, Juan D. Serna

H Tajali, Mostafa Sahrai

In this paper we examine the absorption and dispersion properties of a weak probe field via Electromagnetically Induced Transparency (EIT) in a four-level system. It is shown that under certain condition, using this model, the absorption cancellation is appeared and the medium becomes transparent to the weak probe field. It will be shown that the controlling of absorption and dispersion spectrum depends on some atomic parameters. The effects of quantum interference on the absorption and dispersion spectrum are also investigated

Nikolai S. Bukhman

Yu. M. Golubev, T. Yu. Golubeva, Yuri V. Rostovtsev +1 more

We have shown that quantum interference in a driven quasi-degenerate two-level atomic system can be controlled by an externally applied magnetic field. We demonstrate that the mechanism of optical control is based on quantum interference, which allows one to implement both electromagnetically induced transparency and electromagnetically induced absorption in one atomic system. Dispersion of such the medium allows one to control group velocity of propagation of light pulses be ultra-slow or superluminal via applied magnetic field.

G. S. Agarwal

Various three-level schemes for electromagnetic-field-induced control of absorption are analyzed to isolate the precise nature of the quantum interference. Such interference manifests through the dispersive contributions to the absorption line shapes. Depending on the excitation scheme, the dispersive terms can be either constructive or destructive. The collisional dephasing in some cases can change the nature of interference.

A. P. Khapalyuk