Lattice-enabled detection of spin-dependent three-body interactions

By controllably quenching lattice-confined spinor gases, we experimentally detect coherent three-body interactions, which are often masked by stronger two-body effects, through the induced nonequilibrium spin dynamics. The three-body spin-dependent interaction strengths are precisely extracted via real-time and frequency domain analyses of the observed quench-induced non-equilibrium spin dynamics. Our results demonstrate that the inclusion of the three-body interactions is critical to accurately determine the atom number distribution in lattices with potential applications in quantum sensing via spin singlets. The presented techniques offer a promising avenue for future studies of higher-body interactions with broad relevance to strongly-interacting quantum systems and can be directly applied in other atomic species.