Phenomenon of the Time-reversal-violating Photon Polarization Plane Rotation by a Gas Placed to an Electric Field

1. Violation of time reversal symmetry has been observed only in K0-decay many years ago [1], and remains one of the great unsolved problems in elementary particle physics. Since the discovery of the CP-violation in decay of K0-mesons, a few attempts have been undertaken to observe this phenomenon experimentally in different processes. However, that experiments have not been successful. At the present time novel more precise experimental schemes are actively discussed: observation of the atom [2] and neutron [3] electric dipole moment, T-violating (time reversal) atom (molecule) spin rotation in a laser wave and T-violating optical activity of an atomic or molecular gas [4, 5]. According to [6] the violation of the time reversal symmetry stipulates the appearance of the new optical phenomenon: the photon polarization plane rotation and circular dichroism in an optical homogeneous isotropic matter placed to an electric field. This T-odd phenomenon is the kinematic analog of the famous T-even phenomenon of the photon polarization plane rotation in a matter placed to a magnetic field (Faraday phenomenon). In the present paper T-odd phenomenon of the photon polarization plane rotation (circular dichroism) is considered for an atomic (molecular) gas placed to an electric field. The expression for the T non-invariant polarizability of an atom (molecule) placed to an electric field is obtained. It is shown that the T-odd plane rotation angle θT increases when the interaction energy of an atom (molecule) with an electric field is the same order as the opposite parity levels spacing. 2. In accordance with [4, 5, 6] the T-reversal violating dielectric permittivity tensor εik for an optical diluted matter ( εik − δik ≪ 1, δik is the Kronecker symbol) is given by