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arXiv · 1503.07525

Estimating outcome probabilities of quantum circuits using quasiprobabilities

Hakop Pashayan·Joel J. Wallman·Stephen D. Bartlett
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Abstract

We present a method for estimating the probabilities of outcomes of a quantum circuit using Monte Carlo sampling techniques applied to a quasiprobability representation. Our estimate converges to the true quantum probability at a rate determined by the total negativity in the circuit, using a measure of negativity based on the 1-norm of the quasiprobability. If the negativity grows at most polynomially in the size of the circuit, our estimator converges efficiently. These results highlight the role of negativity as a measure of non-classical resources in quantum computation.

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Hakop Pashayan, Joel J. Wallman, Stephen D. Bartlett. 2015-03-25. Estimating outcome probabilities of quantum circuits using quasiprobabilities. https://doi.org/10.1103/physrevlett.115.070501

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