Kutluer Kutlu, Mazzera Margherita, de Riedmatten Hugues
ICFO-Institut de Ciencies Fotoniques, the Barcelona Institute of Science and Technology, Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain.
ICREA-Institució Catalana de Recerca i Estudis Avançats, 08015 Barcelona, Spain.
Phys Rev Lett. 2017 May 26;118(21):210502. doi: 10.1103/PhysRevLett.118.210502. Epub 2017 May 24.
The generation and distribution of quantum correlations between photonic qubits is a key resource in quantum information science. For applications in quantum networks and quantum repeaters, it is required that these quantum correlations be stored in a quantum memory. In 2001, Duan, Lukin, Cirac, and Zoller (DLCZ) proposed a scheme combining a correlated photon-pair source and a quantum memory in atomic gases, which has enabled fast progress towards elementary quantum networks. In this Letter, we demonstrate a solid-state source of correlated photon pairs with embedded spin-wave quantum memory, using a rare-earth-ion-doped crystal. We show strong quantum correlations between the photons, high enough for performing quantum communication. Unlike the original DLCZ proposal, our scheme is inherently multimode thanks to a built-in rephasing mechanism, allowing us to demonstrate storage of 11 temporal modes. These results represent an important step towards the realization of complex quantum networks architectures using solid-state resources.
光子量子比特间量子关联的产生与分布是量子信息科学中的关键资源。对于量子网络和量子中继器中的应用而言，要求将这些量子关联存储于量子存储器中。2001年，段路明、卢金、西拉克斯和佐勒（DLCZ）提出了一种将关联光子对源与原子气体中的量子存储器相结合的方案，这使得向基本量子网络的快速进展成为可能。在本信函中，我们展示了一种利用稀土离子掺杂晶体的、带有嵌入式自旋波量子存储器的关联光子对固态源。我们展示了光子间强烈的量子关联，其强度足以用于执行量子通信。与最初的DLCZ方案不同，由于内置的重相位机制，我们的方案本质上是多模的，这使我们能够展示11个时间模式的存储。这些结果代表了朝着利用固态资源实现复杂量子网络架构迈出的重要一步。
