1. High-Dimensional Bell Test without Detection Loophole
- Author
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Xiao-Min Hu, Chao Zhang, Bi-Heng Liu, Yu Guo, Wen-Bo Xing, Cen-Xiao Huang, Yun-Feng Huang, Chuan-Feng Li, and Guang-Can Guo
- Subjects
General Physics and Astronomy - Abstract
Violation of Bell's inequalities shows strong conflict between quantum mechanics and local realism. Loophole-free Bell tests not only deepen understanding of quantum mechanics, but are also important foundations for device-independent (DI) tasks in quantum information. High-dimensional quantum systems offer a significant advantage over qubits for closing the detection loophole. In the symmetric scenario, a detection efficiency as low as 61.8% can be tolerated using four-dimensional states and a four-setting Bell inequality [Phys. Rev. Lett. 104, 060401 (2010)PRLTAO0031-900710.1103/PhysRevLett.104.060401]. For the first time, we show that four-dimensional entangled photons violate a Bell inequality while closing the detection loophole in experiment. The detection efficiency of the four-dimensional entangled source is about 71.7%, and the fidelity of the state is 0.995±0.001. Combining the technique of multicore fibers, the realization of loophole-free high-dimensional Bell tests and high-dimensional quantum DI technologies are promising.
- Published
- 2021