Emergent dark states from superradiant dynamics in multilevel atoms in a cavity

We investigate the collective decay dynamics of atoms with a generic multilevel structure (angular momenta F↔F′) coupled to two light modes of different polarization inside a cavity. In contrast to two-level atoms, we find that multilevel atoms can harbour eigenstates that are perfectly dark to cavity decay even within the subspace of permutationally symmetric states (collective Dicke manifold). The dark states arise from destructive interference between different internal transitions and are shown to be entangled.