Brief Introduction

In quantum networks, we established quantum entanglement among three spatially separated quantum nodes by means of storing three entangled optical modes. Besides, we realized long distance entanglement distribution in optical fibers, and 6 km deterministic quantum teleportation. Furthermore, we demonstrated quantum secret sharing among four users based on multipartite bound states. In quantum measurement, we propose and experimentally demonstrate a compact quantum interferometer involving two optical parametric amplifiers and by both squeezing shot noise and amplifying phase-sensing intensity the sensitivity beyond the standard quantum limit is deterministically realized.

Xiaojie Zuo, Zhihui Yan, Yanni Feng, Jingxu Ma, Xiaojun Jia, Changde Xie and Kunchi Peng

We propose and experimentally demonstrate a compact quantum interferometer involving two optical parametric amplifiers and the squeezed states generated within the interferometer are directly used for the phase-sensing quantum state. By both squeezing shot noise and amplifying phase-sensing intensity the sensitivity beyond the standard quantum limit is deterministically realized and a minimum detectable phase smaller than that of all present interferometers under the same phase-sensing intensity is achieved. This interferometric system has significantly potential applications in a variety of measurements for tiny variances of physical quantities.

Phys. Rev. Lett. 124, 173602 (2020)   PDF

Meiru Huo, Jiliang Qin, Jialin Cheng, Zhihui Yan, Zhongzhong Qin, Xiaolong Su, Xiaojun Jia, Changde Xie, and Kunchi Peng

  We experimentally demonstrate deterministic quantum teleportation of an optical coherent state through fiber channels. Two sub-modes of an Einstein-Podolsky-Rosen entangled state are distributed to a sender and a receiver through a 3.0-km fiber, which acts as a quantum resource. The deterministic teleportation of optical modes over a fiber channel of 6.0 km is realized. A fidelity of 0.62 ± 0.03 is achieved for the retrieved quantum state, which breaks through the classical limit of 1/2. Our work provides a feasible scheme to implement deterministic quantum teleportation in communication networks.

Sci. Adv. 4: eaas9401 (2018)  PDF

Yaoyao Zhou, Juan Yu, Zhihui Yan, Xiaojun Jia, Jing Zhang, Changde Xie, and Kunchi Peng

  We design and experimentally demonstrate a quantum secret sharing (QSS) protocol, where the dealer modulates a secret on a four-partite bound entanglement (BE) state and then distributes the submodes of the BE state to four spatially separated players. The presented QSS scheme has the capability to protect secrets from eavesdropping and dishonest players, because a nonlocal and deterministic BE state is shared among four authorized players.

Phys. Rev. Lett. 121, 150502 (2018)  PDF

Zhihui Yan, Liang Wu, Xiaojun Jia, Yanhong Liu, Ruijie Deng, Shujing Li, Hai Wang, Changde Xie, and Kunchi Peng

  We present an experimental demonstration on generation, storage, and transfer of deterministic quantum entanglement among three spatially separated atomic ensembles. The off-line prepared multipartite entanglement of optical modes is mapped into three distant atomic ensembles to establish entanglement of atomic spin waves via electromagnetically induced transparency light–matter interaction. Then the stored atomic entanglement is transferred into a tripartite quadrature entangled state of light, which is space-separated and can be dynamically allocated to three quantum channels for conveying quantum information.

Nature Communications 8,718 (2017)  PDF