Ukrainian Journal of Physics

Influence of Photon Subsystem on the Magnetic Properties of Quantum Gases

M. S. Bulakhov, A. S. Peletminskii, Yu. V. Slyusarenko

Published Sep 18, 2024• 2 citations

Abstract

The possibility for the photon component to affect the magnetic properties of a system of quantum gases of two-level atoms staying in thermodynamic equilibrium with radiation (photons) has been studied. A corresponding simple model has been proposed, which enabled the general equations describing the thermodynamic equilibrium in this system to be derived. The resulting equations are solved in the temperature interval far from the degeneracy temperatures of all three system components. The analysis of the solutions testified to a non-trivial behavior of the system’s magnetic state as a response to changes in the photon density and the intensity of the external magnetic field. It is shown that the growth of the photon density induced in the system by external sources can increase both system’s magnetization and the density of excited atoms. Such a conclusion is not trivial a priori given the fact that photons in the vacuum have no magnetic moment.

DOI: 10.15407/ujpe69.8.600

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