Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore.
Nat Commun. 2013;4:2104. doi: 10.1038/ncomms3104.
The establishment of nonlocal correlations, guaranteed through the violation of a Bell inequality, is not only important from a fundamental point of view but constitutes the basis for device-independent quantum information technologies. Although several nonlocality tests have been conducted so far, all of them suffered from either locality or detection loopholes. Among the proposals for overcoming these problems are the use of atom-photon entanglement and hybrid photonic measurements (for example, photodetection and homodyning). Recent studies have suggested that the use of atom-photon entanglement can lead to Bell inequality violations with moderate transmission and detection efficiencies. Here we combine these ideas and propose an experimental setup realizing a simple atom-photon entangled state that can be used to obtain nonlocality when considering realistic experimental parameters including detection efficiencies and losses due to required propagation distances.
非局域相关性的建立，通过违反贝尔不等式来保证，这不仅从根本上很重要，而且是设备无关量子信息技术的基础。尽管到目前为止已经进行了多项非局域性测试，但它们都存在局域性或检测漏洞的问题。为了克服这些问题，提出了使用原子-光子纠缠和混合光子测量（例如，光电探测和同频探测）的方案。最近的研究表明，使用原子-光子纠缠可以在中等传输和探测效率下导致违反贝尔不等式。在这里，我们结合这些想法，提出了一个实验设置，实现了一个简单的原子-光子纠缠态，可以在考虑到包括探测效率和由于所需传播距离引起的损耗在内的实际实验参数时，获得非局域性。
