Towards non-equilibrium spin dynamics with spin spirals in dense ensembles of NV centers

Exploring far-from-equilibrium systems is an exciting frontier of many-body physics. We present the construction of a new setup to probe many-body dynamics and spin diffusion in long-range interacting spin systems, combining Hamiltonian engineering with spatial control on the scale of the typical NV-NV spacing. We achieve the latter by applying strong magnetic field gradients that can be rapidly switched during the Hamiltonian engineering pulse sequence. In addition to altering the Hamiltonian during the engineering phase, gradients can also prepare non-trivial spin spiral initial states. We estimate that magnetic field gradients on the order of 0.1-1 G/nm are achievable, enabling spin spirals with windings on the order of the spin spacing. Our new experimental apparatus will allow us to study many-body thermalization and the emergence of hydrodynamics in complex many-body quantum systems.