Australian Centre for Quantum-Atom Optics, Department of Quantum Science, The Australian National University, Canberra, ACT 0200, Australia.
Nat Commun. 2012;3:1026. doi: 10.1038/ncomms2033.
Entanglement between large numbers of quantum modes is the quintessential resource for future technologies such as the quantum internet. Conventionally, the generation of multimode entanglement in optics requires complex layouts of beamsplitters and phase shifters in order to transform the input modes into entangled modes. Here we report the highly versatile and efficient generation of various multimode entangled states with the ability to switch between different linear optics networks in real time. By defining our modes to be combinations of different spatial regions of one beam, we may use just one pair of multi-pixel detectors in order to measure multiple entangled modes. We programme virtual networks that are fully equivalent to the physical linear optics networks they are emulating. We present results for N=2 up to N=8 entangled modes here, including N=2, 3, 4 cluster states. Our approach introduces the highly sought after attributes of flexibility and scalability to multimode entanglement.
大量量子模式的纠缠是未来技术（如量子互联网）的关键资源。传统上，在光学中产生多模纠缠需要分束器和相移器的复杂布局，以便将输入模式转换为纠缠模式。在这里，我们报告了具有实时切换不同线性光学网络的能力的各种多模纠缠态的高度通用和高效生成。通过将我们的模式定义为一个光束的不同空间区域的组合，我们可以仅使用一对多像素探测器来测量多个纠缠模式。我们定义了虚拟网络，它们与它们所模拟的物理线性光学网络完全等效。我们在这里介绍了 N=2 到 N=8 个纠缠模式的结果，包括 N=2、3、4 个团簇态。我们的方法为多模纠缠带来了人们高度追求的灵活性和可扩展性的属性。
