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arXiv · 1909.01282

Cross-Platform Verification of Intermediate Scale Quantum Devices

Andreas Elben·Benoît Vermersch·Rick van Bijnen·Christian Kokail·Tiff Brydges·Christine Maier·Manoj Joshi·Rainer Blatt·Christian F. Roos·Peter Zoller
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Abstract

We describe a protocol for cross-platform verification of quantum simulators and quantum computers. We show how to measure directly the overlap $\textrm{Tr}\left[\rho_1 \rho_2\right]$ and the purities $\textrm{Tr}\left[\rho^2_{1,2}\right]$, and thus a fidelity of two possibly mixed quantum states $\rho_1$ and $\rho_2$ prepared in separate experimental platforms. We require only local measurements in randomized product bases, which are communicated classically. As a proof-of-principle, we present the measurement of experiment-theory fidelities for entangled $10$-qubit quantum states in a trapped ion quantum simulator.

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Andreas Elben, Benoît Vermersch, Rick van Bijnen, Christian Kokail, Tiff Brydges, Christine Maier, Manoj Joshi, Rainer Blatt, Christian F. Roos, Peter Zoller. 2019-09-03. Cross-Platform Verification of Intermediate Scale Quantum Devices. https://doi.org/10.1103/physrevlett.124.010504

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