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arXiv · 1408.4382

Quantum annealing correction for random Ising problems

Kristen L. Pudenz·Tameem Albash·Daniel A. Lidar
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Abstract

We demonstrate that the performance of a quantum annealer on hard random Ising optimization problems can be substantially improved using quantum annealing correction (QAC). Our error correction strategy is tailored to the D-Wave Two device. We find that QAC provides a statistically significant enhancement in the performance of the device over a classical repetition code, improving as a function of problem size as well as hardness. Moreover, QAC provides a mechanism for overcoming the precision limit of the device, in addition to correcting calibration errors. Performance is robust even to missing qubits. We present evidence for a constructive role played by quantum effects in our experiments by contrasting the experimental results with the predictions of a classical model of the device. Our work demonstrates the importance of error correction in appropriately determining the performance of quantum annealers.

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Kristen L. Pudenz, Tameem Albash, Daniel A. Lidar. 2015-04-02. Quantum annealing correction for random Ising problems. https://doi.org/10.1103/physreva.91.042302

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