Influence of Free Motion of Atoms on Atomic Density-Dependent Effects in Nonlinear Laser Spectroscopy of Resonant Gas Media
Year: 2023
Type: article
Abstract: We develop a nonlinear theory of propagation of a monochromatic light wave in a gas of two-level atoms under the condition of inhomogeneous Doppler lineshape broadening, while considering a self-consistent solution of the Maxwell–Bloch equations in the mean-field approximation using a single atom density matrix formalism. Our approach shows a significant deformation of the Doppler resonant lineshape (shift, asymmetry), which depends on the atomic density. These effects are a consequence of only the free motion of atoms in a gas and is not associated with interatomic interaction. In particular, the frequency shift of the field-linear contribution to the transmission signal is more than an order of magnitude greater than the shift due to the interatomic dipole–dipole interaction, and the first nonlinear correction has an even stronger deformation, which exceeds the effect of the interatomic interaction by three orders of magnitude. The found effects caused by the free motion of atoms require a significant revision of the existing picture of spectroscopic effects, which depend on the atomic density in a gas.
Institutions: Russian Academy of Sciences, Novosibirsk State University, Institute of Laser Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk State Technical University, All-Russian Scientific Research Institute of Physical-Technical and Radiotechnical Measurements, National Research Nuclear University MEPhI, Centre National de la Recherche Scientifique, Université Paris Sciences et Lettres, Observatoire de Paris, Sorbonne Université, Laboratoire d’Etudes du Rayonnement et de la Matière en Astrophysique et Atmosphères
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4372079614