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arXiv · 1307.1083

Discord in relation to resource states for measurement-based quantum computation

Eleanor G. Rieffel·Howard M. Wiseman
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Abstract

We consider the issue of what should count as a resource for measurement-based quantum computation (MBQC). While a state that supports universal quantum computation clearly should be considered a resource, universality should not be necessary given the existence of interesting, but less computationally-powerful, classes of MBQCs. Here, we propose minimal criteria for a state to be considered a resource state for MBQC. Using these criteria, we explain why discord-free states cannot be resources for MBQC, contrary to recent claims [Hoban et al., arXiv:1304.2667v1]. Independently of our criteria, we also show that the arguments of Hoban et al., if correct, would imply that Shor's algorithm (for example) can be implemented by measuring discord-free states.

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Eleanor G. Rieffel, Howard M. Wiseman. 2014-03-14. Discord in relation to resource states for measurement-based quantum computation. https://doi.org/10.1103/physreva.89.032323

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