Experimental self-testing for photonic graph states

TL;DR

This paper experimentally demonstrates device-independent certification of multipartite graph states using robust self-testing schemes based on scalable Bell inequalities, advancing quantum communication and computation reliability.

Contribution

It provides the first experimental implementation of device-independent certification for multipartite graph states using scalable Bell inequalities.

Findings

Achieved high Bell violation with GHZ and linear cluster states.

Demonstrated certification beyond nontrivial bounds of self-testing schemes.

Paved the way for certification of complex multipartite quantum states.

Abstract

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 the 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.