Freiburg 2019 – scientific programme

Sessions | Days | Selection | Search | Updates | Downloads | Help

FM: Fall Meeting

FM 86: Poster: Secure Communication & Computation

FM 86.2: Poster

Thursday, September 26, 2019, 16:30–18:30, Tents

Tripartite Device-independent Quantum Key Distribution Beyond CHSH Violation — •Timo Holz, Hermann Kampermann, and Dagmar Bruß — Institut für Theoretische Physik III, Heinrich-Heine-Universität Düsseldorf, D-40225 Düsseldorf, Germany

Security proofs for device-independent (DI) quantum key distribution (QKD) rely on a loophole-free violation of Bell inequalities. We introduce a novel Bell inequality including three parties, where each of them measure two dichotomic observables. This Bell inequality functions as a DI witness for genuine tripartite entanglement, given a particular violation is observed. We furthermore present a DIQKD protocol based on the violation of this new Bell inequality. The connection between achievable conference-key rates and the violation of the multipartite Bell inequality is established with the semidefinite programming techniques introduced in Ref. [1]. Thus, our approach goes beyond breaking the multipartite-Bell setting down into an effective bipartite one, violating the Clauser-Horne-Shimony-Holt inequality, and the results of Ref. [2]. We suggest a suitable tripartite QKD protocol and study the effect of different noise models on achievable asymptotic secret-conference-key rates.

[1] L. Masanes et al., Nat. Commun. 2, 238 (2011)

[2] A. Acin et al., Phys. Rev. Lett. 98, 230501 (2007)