Controlled subradiance in atomic arrays

In the CORSAIR project, I propose to study and control subradiance, namely the suppression of collective spontaneous emission, in sub-wavelength arrays of two-level atoms, using a new atomic physics platform. Understanding and controlling how an ensemble of quantum emitters collectively emits or absorbs light is vital in several areas of science and technology. However, the description of this problem is a challenge since it amounts to a dissipative quantum many-body problem. This is why I propose to develop a new experimental research direction towards the following specific objectives: (i) The building of an experimental platform able to create ordered 1D and 2D arrays of atoms with sub-wavelength spacing, and high-fidelity detection of excitations in the arrays. (ii) The selective excitation of subradiant excitations, i.e., where collective spontaneous emission is strongly suppressed. I will develop an addressing scheme to populate a subradiant state with high fidelity and perform experiments demonstrating tailored light storage and retrieval, and metrological enhancement by subradiance. (iii) The understanding of how atomic correlations can be dissipatively engineered via subradiance. I will strive to observe the fermionic correlations that are predicted to emerge from collective decay in arrays, and I will map the phase diagram of a driven two-level atomic array. These objectives will be reached by developing dedicated new tools. I will use dysprosium, an atomic species with properties that allow novel cooling and trapping schemes that I propose to use. In the rich spectrum of Dy, I will isolate a two-level system with a narrow linewidth. I will further develop a novel addressing tool, that allows to drive an array with an alternating phase profile which directly excites a subradiant excitation. I will rely on a broad transition to perform time- and position-resolved high-fidelity measurements of excitations and correlations in the two-level arrays.