Spins associated to optically active defects in diamond provide a promising platform for quantum networks and distributed quantum simulations and computations [1-5]. The defect electron spin can be detected, prepared and measured optically and can be used to create entangled states over long distances . Furthermore, the electron spin can be used to detect and control nuclear spins in its environment, which provide additional quantum bits .
In this talk, I will discuss our recent progress in controlling such electron-nuclear spin systems for quantum networks and for distributed quantum computations and simulations. In particular, I will show that we can image systems with up to 50 nuclear spins with atomic-scale resolution [4,6], and I will discuss how these spins can be used as simulators of many-body physics  and as quantum bits for quantum networks and distributed quantum computation .
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