Screen Shot 2015-01-29 at 4.50.14 PM

Luozhou Li, Tim Schröder, Edward H. Chen, Michael Walsh, Igal Bayn, Jordan Goldstein, Ophir Gaathon, Matthew E. Trusheim, Ming Lu, Jacob Mower, Mircea Cotlet, Matthew L. Markham, Daniel J. Twitchen & Dirk Englund

doi:10.1038/ncomms7173

Abstract:
A central aim of quantum information processing is the efficient entanglement of multiple stationary quantum memories via photons. Among solid-state systems, the nitrogen-vacancy centre in diamond has emerged as an excellent optically addressable memory with second-scale electron spin coherence times. Recently, quantum entanglement and teleportation have been shown between two nitrogen-vacancy memories, but scaling to larger networks requires more efficient spin-photon interfaces such as optical resonators. Here we report such nitrogen-vacancy-nanocavity systems in the strong Purcell regime with optical quality factors approaching 10,000 and electron spin coherence times exceeding 200 μs using a silicon hard-mask fabrication process. This spin-photon interface is integrated with on-chip microwave striplines for coherent spin control, providing an efficient quantum memory for quantum networks.

Related Links:

Coherent spin control of a nanocavity-enhanced qubit in diamond (Nature Communications)

Qubits with staying power (MIT News)

Professor Dirk R. Englund

Quantum Photonics Group