Affiliations 

  • 1 Department of Radiophysics, Kyiv National Taras Shevchenko University, Acad. Glushkova Avenue 4-g, Kyiv 03022, Ukraine
  • 2 State Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
  • 3 Quantum and Laser Science (HIR Building) Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia
J Chem Phys, 2021 Jul 28;155(4):044105.
PMID: 34340365 DOI: 10.1063/5.0054189

Abstract

Quantum optical theory of absorption properties of interacting atoms is developed. The concept of local absorptance is introduced as a derivative of the logarithm of intensity with respect to the distance in the vicinity of a given spatial point and a moment of time. The intensity is represented by the quantum and statistically averaged normal product of creation and annihilation operators of the electromagnetic field. The development of an analytical method of the estimation for the kinetic and optical parameters for the system is proposed here. The calculation method of the absorption coefficient includes thermal atomic motion, Doppler effect, and the short-range interaction between atoms. The absorption coefficient explicitly takes into account the quantum nature of the optical field. The ability of the system to absorb or emit quanta is quantitatively expressed through the special form of interaction integrals. The specific form of integrals results from the structure of the quantum brackets. The interplay between the collective (virtual photon exchange) and binary (optically induced inter-particle bonding) processes determines the system behavior. The spectral profile of the local absorption coefficient for different atomic densities and time intervals is simulated for realistic parameters.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.