Quantum computers are advancing at a rapid pace and are already starting to push the limits of the world's largest supercomputers. Yet, these devices are extremely sensitive to external influences and thus prone to errors which can change the result of the computation. This is particularly challenging for quantum computations that are beyond the reach of our trusted classical computers, where we can no longer independently verify the results through simulation. “In order to take full advantage of future quantum computers for critical calculations we need a way to ensure the output is correct, even if we cannot perform the calculation in question by other means,” says Chiara Greganti from the University of Vienna. A team of physicists from Vienna, Innsbruck, Oxford, and Singapore solves this problem by letting quantum computers check each other. Their findings have been published in PhysRevX.
For more information see:
Cross-verification of independent quantum devices. C. Greganti, T. F. Demarie, M. Ringbauer, J. A. Jones, V. Saggio, I. A. Calafell, L. A. Rozema, A. Erhard, M. Meth, L. Postler, R. Stricker, P. Schindler, R. Blatt, T. Monz, P. Walther, and J. F. Fitzsimons. Physical Review X 2021 DOI: 10.1103/PhysRevX.11.031049
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 801110.
ESQ has received funding from the Austrian Federal Ministry of Education, Science and Research (BMBWF).