Coherent control of quantum systems with phase-stable pulses offers enticing new opportunities for lightwave electronics. Here we extend this approach to many-body systems with spin degrees of freedom, demonstrating that a single few-cycle control pulse can create a sizable population asymmetry between the two degenerate polar ground states of the Ising model. This opens a route for femtosecond-scale data processing and storage, allowing one to control the final ground state of a correlated system in an all-optical way.
Abstract One-dimensional systems exhibiting a continuous symmetry can host quantum phases of matter with true long-range order only in the presence of sufficiently long-range interactions. In most physical systems, however, the interactions are short-ranged, hindering the emergence of such phases in one dimension. Here we use a one-dimensional trapped-ion quantum simulator to prepare states with long-range spin order that extends over the system size of up to
23 spins and is characteristic of the continuous symmetry-breaking phase of matter. Our preparation relies on simultaneous control over an array of tightly focused individual-addressing laser beams, generating long-range spin-spin interactions. We also observe a disordered phase with frustrated correlations. We further study the phases at different ranges of interaction and the out-of-equilibrium response to symmetry-breaking perturbations. This work opens an avenue to study new quantum phases and out-of-equilibrium dynamics in low-dimensional systems.