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arXiv · 1812.11465

Experimental Measurement-Device-Independent Quantum Steering and Randomness Generation Beyond Qubits

Yu Guo·Shuming Cheng·Xiaomin Hu·Bi-Heng Liu·En-Ming Huang·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo·Eric G. Cavalcanti
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Abstract

In a measurement-device-independent or quantum-refereed protocol, a referee can verify whether two parties share entanglement or Einstein-Podolsky-Rosen (EPR) steering without the need to trust either of the parties or their devices. The need for trusting a party is substituted by a quantum channel between the referee and that party, through which the referee encodes the measurements to be performed on that party's subsystem in a set of nonorthogonal quantum states. In this Letter, an EPR-steering inequality is adapted as a quantum-refereed EPR-steering witness, and the trust-free experimental verification of higher dimensional quantum steering is reported via preparing a class of entangled photonic qutrits. Further, with two measurement settings, we extract $1.106\pm0.023$ bits of private randomness per every photon pair from our observed data, which surpasses the one-bit limit for projective measurements performed on qubit systems. Our results advance research on quantum information processing tasks beyond qubits.

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Yu Guo, Shuming Cheng, Xiaomin Hu, Bi-Heng Liu, En-Ming Huang, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo, Eric G. Cavalcanti. 2018-12-30. Experimental Measurement-Device-Independent Quantum Steering and Randomness Generation Beyond Qubits. https://doi.org/10.1103/physrevlett.123.170402

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