Light-Matter Hybrid System in a Tripod Configuration*

The atomic tripod system offers a range of rich dynamics that make it suitable for a number of protocols, such as the optical storage and retrieval of light for quantum memory applications and the implementation of quantum synchronization in a spin-1 system. We present our recent joint theoretical and experimental characterization of a tripod system in a laser-cooled spin-1 ⁸⁷Rb atomic ensemble. In our experiments, a weak probe beam and two control beams couple the four-levels of a tripod system composed of the F = 1 ground state manifold and the F = 0 excited state. As opposed to a three-level lambda configuration, in the tripod system pulsing of the control fields leads to the transfer of the probe optical field to two dark-state polaritons in the ground state manifold, whose dynamics leads to temporal interference in the power of the retrieved probe. We study the impact of tuning the energy levels (through the Zeeman effect) and of the relative phase between the control and probe beams on the retrieved probe and show, both theoretically and experimentally, that the dynamics of the retrieved probe can be controlled. The study of light-matter interactions in such a tripod system allows us to explore diverse hybrid protocols, including a novel approach to measuring synchronization in a spin-1 system.