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arXiv · 1904.10541

Fixed-Depth Two-Qubit Circuits and the Monodromy Polytope

Eric C. Peterson·Gavin E. Crooks·Robert S. Smith
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Abstract

For a native gate set which includes all single-qubit gates, we apply results from symplectic geometry to analyze the spaces of two-qubit programs accessible within a fixed number of gates. These techniques yield an explicit description of this subspace as a convex polytope, presented by a family of linear inequalities themselves accessible via a finite calculation. We completely describe this family of inequalities in a variety of familiar example cases, and as a consequence we highlight a certain member of the "XY-family" for which this subspace is particularly large, i.e., for which many two-qubit programs admit expression as low-depth circuits.

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Eric C. Peterson, Gavin E. Crooks, Robert S. Smith. 2019-04-23. Fixed-Depth Two-Qubit Circuits and the Monodromy Polytope. https://doi.org/10.22331/q-2020-03-26-247

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