Analytical and numerical study of subradiance-only collective decay from atomic ensembles

We analytically and numerically study collective emission from an ensemble of atoms in the weak-excitation regime with the initial condition of uniform excitation of the ensemble. We show that under certain conditions, subradiance at the later stages of the collective decay does not necessarily need to be accompanied by early-time superradiance. We analyze the conditions where such subradiance-only decay occurs for ordered and disordered ensembles in one-, two-, and three-dimensional spatial configurations.