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arXiv · 1610.08529

Contextuality as a resource for models of quantum computation on qubits

Juan Bermejo-Vega·Nicolas Delfosse·Dan E. Browne·Cihan Okay·Robert Raussendorf
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Abstract

A central question in quantum computation is to identify the resources that are responsible for quantum speed-up. Quantum contextuality has been recently shown to be a resource for quantum computation with magic states for odd-prime dimensional qudits and two-dimensional systems with real wavefunctions. The phenomenon of state-independent contextuality poses a priori an obstruction to characterizing the case of regular qubits, the fundamental building block of quantum computation. Here, we establish contextuality of magic states as a necessary resource for a large class of quantum computation schemes on qubits. We illustrate our result with a concrete scheme related to measurement-based quantum computation.

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Juan Bermejo-Vega, Nicolas Delfosse, Dan E. Browne, Cihan Okay, Robert Raussendorf. 2017-09-25. Contextuality as a resource for models of quantum computation on qubits. https://doi.org/10.1103/physrevlett.119.120505

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