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Wigner function negativity and contextuality in quantum computation on rebits

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 نشر من قبل Robert Raussendorf
 تاريخ النشر 2014
  مجال البحث فيزياء
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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 Hudsons theorem. We introduce contextuality witnesses for rebit states, and discuss the compatibility of our result with state-independent contextuality.



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