NEOVITA · Non-equilibrium optically levitated interacting nanoparticle arrays

We propose the exploration of many-body quantum physics with a new experimental platform, based on theoptically levitated and cooled arrays of spherical nanoparticles with strong and controllable interactions. Therecent works by the host institution demonstrated the cavity assisted cooling of a single nanoparticle to itsmotional quantum ground state as well as the simultaneous trapping of two nanoparticles with full controlover the interactions between them. In this work we shall extend these results to the multiple particles. Thiswill be on the one hand an important milestone towards achieving the many-body regime and on the otherhand, the first observation of the cavity assisted cooling of an array of nanoparticles via coherent lightscattering. The realisation of this milestone will enable us to study the system’s non-equilibrium relaxation afterprecise perturbation protocols. Using the natural isolation from the environment, we shall study thethermalisation of a nearly isolated few-particle quantum system. Depending on the energetic landscape, as wellas on the nature and range of interactions, we expect to observe motional pre-thermalisation, or the absenceof thermalisation with the onset of the Anderson localisation or the Many-Body Localisation of phonons. Finally,we shall explore the controllable non-reciprocity of the inter-particle interactions by breaking the directionalsymmetry of the inter-particle forces by conferring to them the direction dependent phases. Combining thiswith the dissipative nature of these forces, we aim at implementing a specifically tailored non-hermitianHamiltonian describing the constant intensity waves.