Focusing of radiation trapped in an anisotropic resonance medium

A. I. Alekseev, Nikitin IuP

R. I. Sokolovskiǐ

V. E. Khartsiev, V. M. Ovchinńikov

Igor V. Kazinets, Boris G. Matisov, Alexander Yu. Snegirev

The propagation of two-component laser radiation in a medium consisting of atoms with a Λ level scheme is investigated. The simultaneous self-focusing of two beams is considered. The main features of this phenomenon are: 1) lowering of the self-focusing threshold by several orders of magnitude in comparison with the known case of saturation of a transition in a two-level atom; 2) a strong dependence of the character of the propagation of the radiation on the difference between the detunings of the two frequency components of the field from resonance, which is associated with fulfillment of the two-photon resonance condition.

Yu. A. Vdovin, V. M. Ermachenko

Marjan Jafari

Cherenkov radiation is one of the problems in light- matter interaction that can be opened new ideas in quantum electrodynamic. A quantum mechanic approach is presented for Cherenkov radiation of a moving atom in uniaxial and biaxial anisotropic medium. A moving particle in a medium emits Cherenkov radiation when its speed be larger than the phase velocity of light in the medium. The electromagnetic field is quantized in the anisotropic media, using maxwell and related constitute equations, phenomenologically. The Cherenkov radiation for an moving charged particle in the anisotropic medium with arbitrary real permittivity tensor is obtained. The dielectric structure can be changed the Cherenkov radiation. For uniaxial media, we give a close form of the Cherenkov radiation for arbitrary dipole alignment. In this manner, the Cherenkove radiation of the biaxial media is calculated.. It is shown the Cherenkov radiation in an isotropic medium can be obtained from the form of an anisotropic medium.