Non-local Stabilization and Synchronization of Larmor Precession in Trapped Polariton Condensate Dimer

We demonstrate mutual synchronization of Larmor precessions between spatially separated, optically trapped polariton condensates. We identify the cross-condensate correlation g(2)1,2(τ) as a sensitive metric for condensate coupling. Synchronization of precessions in a condensate dimer is mediated by polariton outflow and resonantly depends on spectral overlap and precession winding. All-optical stirring of one site non-locally increases the pseudo-spin dephasing time of its static neighbor, prolonging phase-locking in a dimer by an order of magnitude. Our work establishes a scalable platform for studying non-equilibrium time-periodically driven systems and for high-speed spinoptronic networks.