Experimental self-testing for photonic graph states
Jia-Min Xu, Qing Fa Zhou, Yuxiang Yang, Zi-Mo Cheng, Xin-Yu Xu, Zhi‐Cheng Ren, Xi‐Lin Wang, Hui‐Tian Wang · Optics Express · 2021
Graph states-one of the most representative families of multipartite entangled states-are important resources for multiparty quantum communication, quantum error correction, and quantum computation. Device-independent certification of highly entangled graph states plays a prominent role in quantum information processing tasks. Here we have experimentally demonstrated device-independent certification for multipartite graph states by adopting the robust self-testing scheme based on scalable Bell inequalities. Specifically, the prepared multi-qubit Greenberger-Horne-Zeilinger (GHZ) states and linear cluster states achieve a high degree of Bell violation, which are beyond the nontrivial bounds of the robust self-testing scheme. Furthermore, our work paves the way to the device-independent certification of complex multipartite quantum states.