title: Secret Sharing of a Quantum State.
abstract: Secret sharing of a quantum state, or quantum secret sharing, in which a dealer wants to share a certain amount of quantum information with a few players, has wide applications in quantum information. The critical criterion in a threshold secret sharing scheme is confidentiality: with less than the designated number of players, no information can be recovered. Furthermore, in a quantum scenario, one additional critical criterion exists: the capability of sharing entangled and unknown quantum information. Here, by employing a six-photon entangled state, we demonstrate a quantum threshold scheme, where the shared quantum secrecy can be efficiently reconstructed with a state fidelity as high as 93%. By observing that any one or two parties cannot recover the secrecy, we show that our scheme meets the confidentiality criterion. Meanwhile, we also demonstrate that entangled quantum information can be shared and recovered via our setting, which shows that our implemented scheme is fully quantum. Moreover, our experimental setup can be treated as a decoding circuit of the five-qubit quantum error-correcting code with two erasure errors.
authors.affiliation: Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS-Alibaba Quantum Computing Laboratory, Shanghai 201315, China.
authors.forename: He
authors.initials: H
authors.lastname: Lu
authors.affiliation: Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS-Alibaba Quantum Computing Laboratory, Shanghai 201315, China.
authors.forename: Luo-Kan
authors.initials: LK
authors.lastname: Chen
authors.affiliation: Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS-Alibaba Quantum Computing Laboratory, Shanghai 201315, China.
authors.forename: Zheng-Da
authors.initials: ZD
authors.lastname: Li
authors.affiliation: Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS-Alibaba Quantum Computing Laboratory, Shanghai 201315, China.
authors.forename: Chang
authors.initials: C
authors.lastname: Liu
authors.affiliation: Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS-Alibaba Quantum Computing Laboratory, Shanghai 201315, China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS-Alibaba Quantum Computing Laboratory, Shanghai 201315, China.
authors.forename: Nai-Le
authors.initials: NL
authors.lastname: Liu
authors.affiliation: Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: Xiongfeng
authors.initials: X
authors.lastname: Ma
authors.affiliation: Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS-Alibaba Quantum Computing Laboratory, Shanghai 201315, China.
authors.forename: Yu-Ao
authors.initials: YA
authors.lastname: Chen
authors.affiliation: Shanghai Branch, National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.|CAS-Alibaba Quantum Computing Laboratory, Shanghai 201315, China.
authors.forename: Jian-Wei
authors.initials: JW
authors.lastname: Pan