Photonic graph states are underlying resources for one-way optical quantum computation, quantum error correction, fundamental testing of quantum mechanics, and quantum communication networks. Most existing works, however, are based on the spontaneous parametric down-conversion sources that intrinsically suffer from probabilistic generation and double pair components. Here, we create two important classes of graph states, a polarization-encoded four-photon Greenberger–Horne–Zeilinger (GHZ) state and a linear cluster state, by actively demultiplexing a deterministic single-photon source from a semiconductor quantum dot embedded in a micropillar. A state fidelity of 0.790 ± 0.009 (0.763 ± 0.004) and a count rate of ∼13 Hz are observed for the four-photon GHZ (cluster) state. The results constitute a new route toward the multiphoton entanglement with deterministic single-photon sources.

中文翻译：

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来自固态单光子源的多光子图状态

光子图状态是单向光学量子计算，量子纠错，量子力学的基础测试以及量子通信网络的基础资源。但是，大多数现有的工作都是基于自发的参数下转换源，这些源固有地受到概率生成和双对分量的影响。在这里，我们通过积极地将确定性单光子源从嵌入在半导体器件中的半导体量子点中解复用，来创建两类重要的图形状态：偏振编码的四光子格林伯格-霍恩-策林格（GHZ）状态和线性簇状态。微柱。对于四光子GHZ（群集）状态，观察到的状态保真度为0.790±0.009（0.763±0.004），计数率为〜13 Hz。