Light-induced magnetization of an atomic gas

A.I. Alekseev

A. I. Alekseev

A. I. Alekseev

The optically induced magnetic moment of a stationary atom is calculated as a function of time and the resonance detuning ω-ω ba to within a constant factor having the dimensions of a magnetic moment based on the symmetry of an atom in the field of a resonant light pulse and symmetry with respect to time reversal including the initial conditions. The even dependence of the optically induced magnetic moment on ω-ω ba for an elliptically polarized pulse with an isotropic initial state of the atom and its odd dependence on ω-ω ba in the case of a linearly polarized pulsed with an anisotropic initial state in the atom’s alignment are shown to be consequences of symmetry with respect to time reversal and the initial conditions. This behavior is retained even after passage of the light pulse, when the resulting relaxation destroys the time reversal symmetry. The optically induced magnetization of an atomic gas is found to have analogous properties.

S. E. Skipetrov, Igor M. Sokolov

We discover a transition from extended to localized quasimodes for light in a gas of immobile two-level atoms in a magnetic field. The transition takes place either upon increasing the number density of atoms in a strong field or upon increasing the field at a high enough density. It has many characteristic features of a disorder-driven (Anderson) transition but is strongly influenced by near-field interactions between atoms and the anisotropy of the atomic medium induced by the magnetic field.

A. I. Alekseev, M. E. Alferieff

A. I. Alekseev, N. A. Korotkova