Australian and North American physicists display rigorous, scalable diagnostic tool.
Noise is the main obstacle to building large-scale quantum computers. To tame the noise (interference or instability), scientists need to understand how it affects an entire quantum system.
Until now this information was only available for very small devices or subsets of devices.
Work by Dr. Robin Harper and colleagues published today in Nature Physics develops algorithms that will work across large quantum devices.
They demonstrate this by diagnosing the noise in an IBM Quantum Experience device, discovering correlations in the 14-qubit machine not previously detected.
Dr. Harper said: “The results are the first implementation of provably rigorous and scalable diagnostic algorithms capable of being run on current quantum devices and beyond.”
Reference: “Efficient learning of quantum noise” by Robin Harper, Steven T. Flammia and Joel J. Wallman, 10 August 2020, Nature Physics.
Dr. Harper is a postdoctoral researcher at the University of Sydney Nano Institute and part of the Australian Research Council Centre of Excellence for Engineered Quantum System