Dipole-dipole interaction of levitated nanoparticles
Arrays of optically trapped nanoparticles have emerged as a platform for the study of complex nonequilibrium phenomena. Analogous to atomic many-body systems, one of the crucial ingredients is the ability to precisely control the interactions between particles. However, the optical interactions studied thus far only provide conservative optical binding forces of limited tunability.
In this talk I will present results ways to exploit the phase coherence between the optical fields that drive the light-induced dipole-dipole interaction to couple two nanoparticles, and freely tune the interactions. These can be, based on recent results, fully nonreciprocal, allowing the breaking of parity-time symmetry and observation of mechanical lasing transitions.
Our results provide a route to developing fully programmable many-body systems of interacting nanoparticles with tunable nonreciprocal interactions, which are instrumental for exploring entanglement and topological phases in arrays of levitated nanoparticles.