Tailored optical properties of an atomic medium by a narrow-bandwidth frequency comb

Abstract

The quantum-interference-assisted enhanced optical activity due to the emergence of a steady-state atomic polarization is investigated. Rubidium atoms in an antirelaxation-coated cell provide a suitable platform to address the phenomena at multiple Larmor frequencies. The atomic sample interacts with a narrow-bandwidth frequency comb generated by the frequency modulation of the light field. The Lindblad master equation with a trichromatic field provides a microscopic picture of the atomic response to the narrow-bandwidth frequency comb. The directive of the relative phase between the light fields, in the detuning dependence of the magnetic resonances, is conclusively captured with the trichromatic field model. The measured absorption, nonlinear magneto-optic rotation, and their dependencies on various experimental parameters are analyzed. Ellipticity of the light field controls the extent of several physical processes at multiple Larmor frequencies. The investigation provides an approach to address the Zeeman coherence in the interaction of a narrow bandwidth frequency comb with an atomic ensemble and will have applications in various quantum devices.