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arXiv · 1603.03672

Randomized gap and amplitude estimation

Ilia Zintchenko·Nathan Wiebe
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Abstract

We provide a method for estimating spectral gaps in low-dimensional systems. Unlike traditional phase estimation, our approach does not require ancillary qubits nor does it require well characterised gates. Instead, it only requires the ability to perform approximate Haar-random unitary operations, applying the unitary whose eigenspectrum is sought out and performing measurements in the computational basis. We discuss application of these ideas to in-place amplitude estimation and quantum device calibration.

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Ilia Zintchenko, Nathan Wiebe. 2016-03-11. Randomized gap and amplitude estimation. https://doi.org/10.1103/physreva.93.062306

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