Observation of σ–π coupling and mode selection in optically trapped artificial polariton molecules

Microcavity exciton–polariton condensates under additional transverse confinement constitute a flexible optical platform to study the coupling and hybridization between neighboring nonlinear states of light and matter. Driven far from equilibrium, networks of polariton condensates can display spontaneous synchronization, pattern formation, and instabilities depending on the excitation and material parameters. Here, we investigate this coupling mechanism between polariton condensates populating the first excited p -state manifold in optical traps and show a rich structure of patterns based on excitation parameters. Spontaneous symmetry breaking in the p -orbital manifold upon condensation results in an ordered arrangement of dipole-shaped condensates between coupled traps reminiscent of σ and π molecular bonding mechanisms but restricted to the plane. A salient advantage is offered by the optical reconfigurability of the laser excitation patterns, which determine the parameters of the polariton trapping potential and coupling strength with neighboring condensates. Our results underpin the potential role of polariton condensates in exploring the conditions of spontaneous order in the relative orientation of anisotropic nonlinear states of light and matter.