Dynamical excitation control and multimode emission of an atom-photon bound state

Atom-photon bound states emerge when an atom couples to a metamaterial, offering a platform for long-range interactions crucial to quantum technologies. This work experimentally investigates their formation and radiative nature by analyzing the emitted light, revealing the underlying energy structure. The approach introduces a powerful new method to probe internal dynamics of bound states, demonstrated here for the first time, and extends beyond the insights of previous studies.