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Robust and parsimonious realisations of unitaries in the one-way model

Vincent Danos·Elham Kashefi·Prakash Panangaden
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Abstract

We present a new set of generators for unitary maps over \otimes^n(C^2) which differs from the traditional rotation-based generating set in that it uses a single-parameter family of 1-qubit unitaries J(a), together with a single 2-qubit unitary controlled-Z. Each generator is implementable in the one-way model using only two qubits, and this leads to both parsimonious and robust implementations of general unitaries. As an illustration, we give an implementation of the controlled-U family which uses only 14 qubits, and has a 2-colourable underlying entanglement graph (known to yield robust entangled states).

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Vincent Danos, Elham Kashefi, Prakash Panangaden. 2004-11-10. Robust and parsimonious realisations of unitaries in the one-way model. https://doi.org/10.1103/physreva.72.064301

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