Dark-Soliton Molecules in an Exciton-Polariton Superfluid
Anne Maître, Giovanni Lerario, Adrià Medeiros, Ferdinand Claude, Quentin Glorieux, Elisabeth Giacobino, Simon Pigeon, Alberto Bramati
Abstract
The general theory of dark solitons relies on repulsive interactions and, therefore, predicts the impossibility to form dark-soliton bound states. One important exception to this prediction is the observation of bound solitons in nonlocal nonlinear media. Here, we report that exciton-polariton superfluids can also sustain darksoliton molecules, although the interactions are fully local. With a novel all-optical technique, we create two dark solitons that bind together to form an unconventional dark-soliton molecule. We demonstrate that the stability of this structure and the separation distance between two dark solitons is tightly connected to the driven-dissipative nature of the polariton fluid.