Impact of Quantum Error Correction on Performance

A new paper from scientists at USC demonstrates the performance benefits of quantum error correction on a quantum annealing system like D-Wave. The USC team used the Lockheed Martin D-Wave Two housed there. The abstract of the paper is as follows:

"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."

Here is a link to the paper: http://arxiv.org/pdf/1408.4382v1.pdf

As we have talked about in previous blog posts, performance of D-Wave systems is not just related to the number of qubits but other factors like the interconnectivity of qubits, temperature and noise reduction, precision and accuracy of problem parameters and more.  A previous post discusses this in more detail: http://www.dwavesys.com/blog/2014/03/scaling-quantum-systems

Regards,

Susan Davis, D-Wave Marketing