Interaction of polarized waves in a three-level medium

V. G. Dubovets

A. Zh. Muradyan, L. Petrosyan

A change in the polarization of an ultrashort light pulse is induced by a strong polarized pulse when the two pulses interact with three-level atoms in a gaseous medium with arbitrary values of the momentum. An analysis is made of the possibility of increasing the output signal (i.e., the amplitude of Cartesian component of a probe wave rotated by 90°) by modulation of the input wave phase in accordance with oscillations of a coherent-transient response of the gaseous medium.

Pavel A Apanasevich, V. G. Dubovets

G. G. Adonts, J.N. Elgin

The propagation of strongly polarized electromagnetic waves through a resonance medium, with arbitrary angular momenta of the levels, is investigated in the adiabatic-following approximation. Exact wavefunctions of the two-level atomic system with degenerate levels in the field of a circularly (linearly) polarized wave are constructed and the picture of the shift of energy level splittings is discussed. Exact formulae for the nonlinear refractive index of the medium in the field of the circularly (linearly) polarized wave are found. The propagation of counterpropagating polarized waves—an intense pump wave and a probe light signal—through the resonance medium is studied. The studies are carried out in the scope of a two-level (one-photon resonance) and a three-level (one- and two-photon resonances) medium. Formulae are found for the induced rotation of the plane of polarization for the probing signal that are exact in terms of the intensity of the pump wave. The spectral dependence of the angle of rotation is studied, and it is shown that a series of Stark-shifted resonance poles of atomic absorption and a three-photon scattering process arise.

Ashat M. Basharov, Andrei I. Maimistov

G. G. Adonts, Eghine G. Kanetsyan

The interaction of elliptically polarized radiation with a resonant medium consisting of atoms with an excited state split into a doublet was studied theoretically. Interference terms associated with the coherent interaction of the field with the excited sublevels of the doublet were found to appear in the refractive index. The dispersion dependence of the refractive index was studied. It was shown that the decay constants for the multipole moments of the current of a dipole-forbidden atomic transition can be determined by the choice of the wave polarization.