Shift and Splitting of Atomic Energy Levels by the Field of an Electromagnetic Wave

Osamu Hara, T. Tokano

Jingtao Zhang, Feng Xun-Li, Xu Zhi-Zhan

The emission spectra of a two-level atom moving in an electromagnetic field are studied. We find that there is a shift in the peak position and that each peak splits into double peaks. The shift is due to the detuning induced by the atomic motion, and the splitting is caused by the atomic energy change due to the exchange of photons.

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.

John Stuart Foster

V. N. Streltsov

Mikhail Vladimirovich Fedorov

An analysis is made of the Stark effect in a hydrogen atom subjected to a static electric field and the field of a strong resonant electromagnetic wave. It is shown that the resonant interaction modifies the linear (with respect to the static field intensity) splitting of the atomic levels and gives rise to a quadratic shift of sublevels.