2015 CAP Congress / Congrès de l'ACP 2015

Wigner function negativity and contextuality in quantum computation on rebits

17 Jun 2015, 13:45

30m

CAB 239 (University of Alberta)

Invited Speaker / Conférencier invité Condensed Matter and Materials Physics / Physique de la matière condensée et matériaux (DCMMP-DPMCM) W2-2 Quantum Information and Quantum Computation (DTP-DCMMP) / Information et calcul quantique (DPT-DPMCM)

Speaker

Robert Raussendorf (UBC)

Description

We describe a universal scheme of quantum computation by state injection on rebits (states with real density matrices). For this scheme, we establish contextuality and Wigner function negativity as computational resources, extending results of [M. Howard et al., Nature 510, 351–355 (2014)] to two-level systems. For this purpose, we define a Wigner function suited to systems of n rebits, and prove a corresponding discrete Hudson’s theorem. We introduce contextuality witnesses for rebit states, and discuss the compatibility of our result with state-independent contextuality.