Quantum information processing with nuclear spins in diamond
Abstract: Spins associated to defects in solids are promising qubits for quantum information processing. We have developed novel control gates for an electron spin coupled to nuclear spins, and applied this scheme to realise a universally connected 10-qubit register using an NV-centre in diamond . Moreover, we employed dynamical decoupling of the register to realise coherence times up to 63(2) seconds. Building upon these techniques, we have also recently demonstrated the 3D imaging of a system of 27 coupled nuclear spins with atomic scale resolution . I will discuss these results, alongside the outlook for implementing advanced quantum algorithms and quantum simulations of many body physics in this system. Scaling this platform to larger numbers of qubits might be achieved by combining small registers of qubits through photonic links  in a modular fashion. I will show how the use of isotopic engineering enables a dramatic improvement in data qubit robustness during probabilistic entanglement generation, paving the way for complex network protocols.
 C. E. Bradley*, J. Randall*, M. H. Abobeih, R. C. Berrevoets, M. J. Degen, M. A. Bakker, M. Markham, D. J. Twitchen, and T. H. Taminiau, Phys. Rev. X 9, 031045 (2019)
 M. H. Abobeih, J. Randall, C. E. Bradley, H. P. Bartling, M. A. Bakker, M. J. Degen, M. Markham, D. J. Twitchen, T. H. Taminiau, Nature 576, p 411–415 (2019)
 P. C. Humphreys, N. Kalb, J. P. J. Morits, R. N. Schouten, R. F. L. Vermeulen, D. J. Twitchen, M. Markham, R. Hanson, Nature 558, 268-273 (2018)