Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA.
Nat Commun. 2015 Jan 28;6:6173. doi: 10.1038/ncomms7173.
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.
量子信息处理的一个主要目标是通过光子有效地纠缠多个静止的量子存储器。在固态系统中，金刚石中的氮空位中心已成为具有二阶电子自旋相干时间的出色光学可寻址存储器。最近，已经在两个氮空位存储器之间展示了量子纠缠和量子隐形传态，但是要扩展到更大的网络，则需要更有效的自旋-光子接口，例如光学谐振器。在这里，我们使用硅硬掩模制造工艺报告了处于强Purcell 区的这种氮空位-纳米腔系统，其光学品质因数接近 10,000，电子自旋相干时间超过 200μs。该自旋-光子接口与片上微波带状线集成在一起，用于相干自旋控制，为量子网络提供了高效的量子存储器。
