Solid State Quantum Networks (SSQN)

固态量子网络 (SSQN)

• 批准号: EP/J007994/1
• 负责人: John Rarity
• 金额: $ 37.19万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FJ007994%2F1
• 关键词: Solid; State; Quantum; Networks; SSQN

Quantum communication, the transfer of quantum superposition states over long distances, is presently limited to about 200km (both in optical fibre and free space) due to unavoidable photon absorption losses. For this reason, theoretical schemes to extend this distance using "entanglement swapping" and "teleportation" have been established. By concatenating short entanglement swapping sub-sections it is in principle possible to generate entangled (correlated) bits over very long distances with bit rate only limited by the losses in one short section. If realised this would extend quantum communication applications such as quantum cryptography and quantum teleportation out to distances of thousands of kilometres.In this consortium we propose to work towards such a deterministic quantum network based on semiconductor quantum dot-micropillar cavity systems. We will generate entangled photon sources from the biexciton-exciton cascade of a quantum dot (QD), with a potential fidelity of >90%. Moreover, we will develop a QD-spin micropillar cavity system, which acts as an all-in-one spin-photon-interface and a Bell-state analyser. This component eliminates the need for synchronous arrival of the two photons, and allows a wait-until-success protocol over the timescale of the spin coherence time (microseconds to milliseconds). Further subcomponents will include electro-optically tuneable single photon sources and recently proposed sequentially entangled sources.With this suite of subcomponents we will be able to realise all the functions required for a scalable quantum network including the final entanglement purification steps. This is in contrast to previous experimental demonstrations of entanglement swapping (and teleportation) which were probabilistic and thus unscalable.The project involves collaboration between four partners. We will bring together two world-class groups, LPN and Würzburg (UWUERZ), working on micropillar cavities producing highly efficient entangled pair sources (LPN), and strongly-coupled QD-spin-cavity systems (UWUERZ), with the aim of addressing the challenging issues of entangled-pair sources and spin-cavity systems. Theoretical support for novel and practical entanglement schemes will be provided by Imperial College (IMP), and the experimental implementation will be performed by Bristol (BRIS) and LPN, who have world-class expertise in quantum optical communication , QD spins and semiconductor microcavity quantum electro-dynamics.

量子通信，即量子叠加态在长距离上的传输，由于不可避免的光子吸收损失，目前仅限于约200公里（在光纤和自由空间中）。因此，利用“纠缠交换”和“隐形传态”来延长这个距离的理论方案已经建立。通过连接短纠缠交换子部分，原则上可以在非常长的距离上生成纠缠（相关）比特，其中比特率仅受一个短部分中的损耗的限制。如果实现，这将扩展量子通信的应用，如量子密码学和量子隐形传态到数千公里的距离。在这个联盟中，我们建议努力实现这样一个确定性的量子网络的基础上半导体量子点微柱腔系统。我们将从量子点的双激子-激子级联中产生纠缠光子源，其潜在保真度大于90%。此外，我们将发展一个量子点自旋微柱腔系统，作为一个多合一的自旋光子界面和贝尔态分析器。该组件消除了对两个光子同步到达的需要，并且允许在自旋相干时间的时间尺度（微秒到毫秒）上等待直到成功的协议。进一步的子组件将包括电光可调谐单光子源和最近提出的顺序纠缠源。有了这套子组件，我们将能够实现可扩展量子网络所需的所有功能，包括最终的纠缠纯化步骤。这与之前的纠缠交换（和隐形传态）实验演示形成了鲜明对比，这些实验演示是概率性的，因此无法扩展。我们将汇集两个世界级的团队，LPN和维尔茨堡（UWUERZ），致力于生产高效纠缠对源（LPN）和强耦合QD自旋腔系统（UWUERZ）的微柱腔，旨在解决纠缠对源和自旋腔系统的挑战性问题。新的和实用的纠缠方案的理论支持将由帝国理工学院（IMP）提供，实验实施将由布里斯托（BRIS）和LPN进行，他们在量子光通信，量子点自旋和半导体微腔量子电动力学方面具有世界一流的专业知识。

项目成果

Photonic transistor and router using a single quantum-dot-confined spin in a single-sided optical microcavity.

• DOI: 10.1038/srep45582
• 发表时间: 2017-03-28
• 期刊: Scientific reports
• 影响因子: 4.6
• 作者: Hu CY

Structured polymer waveguides on distributed Bragg reflector coupling to solid state emitter

• DOI: 10.1088/2040-8986/aa6a70
• 发表时间: 2017-05
• 期刊: Journal of Optics
• 影响因子: 2.1
• 作者: S. Knauer;M. López-García;J. Rarity

Polymer photonic microstructures for quantum applications and sensing

用于量子应用和传感的聚合物光子微结构

• DOI: 10.1109/nusod.2016.7547049
• 发表时间: 2016
• 作者: Knauer S

Proposal for a loophole-free Bell test based on spin-photon interactions in cavities

• DOI: 10.1088/1367-2630/15/10/105006
• 发表时间: 2013-10-08
• 期刊: NEW JOURNAL OF PHYSICS
• 影响因子: 3.3
• 作者: Brunner, Nicolas;Young, Andrew B.;Rarity, John G.
• 通讯作者: Rarity, John G.

Spin-based single-photon transistor, dynamic random access memory, diodes, and routers in semiconductors

• DOI: 10.1103/physrevb.94.245307
• 发表时间: 2016-12-14
• 期刊: PHYSICAL REVIEW B
• 影响因子: 3.7
• 作者: Hu, C. Y.