Spectral line collapse as a result of radiation-induced transfer of polarization

Sergey G. Rautian

B. A. Veklenko, Ganna Tkachuk

M. B. Gornyi, D. L. Markman, Boris G. Matisov

Sergei A. Akhmanov, S YU Nikitin

Abstract From the dynamics of an oscillator to the statistics of an ensemble. Non-laser sources of light: intensity, polarization, and radiation directivity pattern. Radiation statistics of independent oscillators. The radiation spectrum. Mechanisms of spectral line broadening. Natural broadening. Doppler broadening. Collision-induced broadening and the shift of a spectral line. Dicke’s effect: collision-induced narrowing of a Doppler spectral line in a dense gas.

Peter M. Selzer, William M. Yen

The first direct observation of radiative spectral transfer within an inhomogeneously broadened line (the R(1) line of ruby) is reported. As opposed to nonradiative transfer, the temperature dependence of the radiative process is consistent with exponential, in agreement with recent predictions. A temperature-independent, resonant process is also directly observed. The implication of these results for the concept of microscopic strain broadening is discussed.

Marina Movsisyan, Svetlana Shmavonyan, A. Papoyan

Abstract We present the results of spectroscopic and polarization studies of dilute rubidium vapor exposed to a single-frequency linearly polarized diode laser radiation in a spectral range of atomic D2 line. We report the origin of a circularly polarized radiation on V-type transitions of 87Rb F g = 2 → F e = 3 and 85Rb F g = 3 → F e = 4, and amplification of this radiation in backward direction caused by a partial population inversion among magnetic sublevels of the ground and excited levels. This is confirmed experimentally by high directivity of backward radiation, absence in its spectrum of 85Rb F g = 2 → F e = 1 (Λ-type) radiation, as well as by different nature of intensity dependences of backward and fluorescence radiations.