Enhanced transport of two interacting quantum walkers in a one-dimensional quasicrystal with power-law hopping

We report a robust delocalization transition of a pair of hard-core bosons moving in a one-dimensional quasicrystal with power-law hopping. We find that in the regime of strong interactions quasiperiodicity first suppresses the transport, as in the usual Anderson picture, and then, transport is enhanced when the quasiperiodic modulation is increased. By introducing an effective Hamiltonian, valid for strong interactions, we unveil the mechanism behind the delocalization transition. Stationary single-particle properties, as well as two-particle correlations, confirm all of our findings. Extensive numerical calculations lead us to establish the values of quasiperiodic modulation, interparticle interactions, and power hops for which the delocalization takes place. Our results are of direct relevance to current experiments of systems with long-range interactions.