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QUANTUM COMPUTING

Variational unsampling

Nature Reviews Physics volume 2, page 72 (2020)Cite this article

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The probability distribution to be sampled comes from the output of a quantum circuit that is fed a known initial state. In sampling algorithms, the unitary operation implemented by the quantum circuit is known and one is interested in the output or final state. In the unsampling algorithm, the task is to learn as much as possible about the unitary operation given a polynomial number of outputs and the known initial state. Carolan and colleagues showed how to do this using a variational approach that solves an optimization problem by efficiently exploring the associated Hilbert space. This protocol is hardware independent and can be used not only for verifying quantum computation, but also for characterizing unknown physical processes.

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  1. Nature Reviews Physics https://www.nature.com/natrevphys/

    Iulia Georgescu

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  1. Iulia Georgescu
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Correspondence to Iulia Georgescu.

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Georgescu, I. Variational unsampling. Nat Rev Phys 2, 72 (2020). https://doi.org/10.1038/s42254-020-0147-y

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