Room-Temperature Slow Light in a Coupled Cavity Magnon-Photon System

Realizing room-temperature slow light is of fundamental importance in physics and may promote the practical applications of slow light in information storage and optical communication. Here, we propose a feasible way to realize room-temperature slow light based on magnon-polaritons in a coupled cavity magnon-photon system, in which the cavity microwave photons strongly coupling with the magnons in a small-scale magnetic insulator yttrium-iron-garnet (YIG, Y
₃
Fe
₅
O
₁₂
). We find that the generation of slow light does not require the harsh conditions of ultra-low temperature, and the magnitude of the group delay can be regulated by adjusting the external magnetic field. Furthermore, the transformation between the fast and slow light can be achieved by controlling the magnon-photon coupling strength. Based on the current experimental condition, we believe that the proposed scheme of room-temperature slow light will be highly accessible in experiments. The potential applications range from enhancing magnon-photon interaction to designing an optical communication network.