Rolling quantum dice with a superconducting qubit

R. Barends; J. Kelly; A. Veitia; A. Megrant; A. G. Fowler; B. Campbell; Y. Chen; Z. Chen; B. Chiaro; A. Dunsworth; I. -C. Hoi; E. Jeffrey; C. Neill; P. J. J. O'Malley; J. Mutus; C. Quintana; P. Roushan; D. Sank; J. Wenner; T. C. White; A. N. Korotkov; A. N. Cleland; John M. Martinis

doi:10.1103/physreva.90.030303

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arXiv · 1406.3364

Rolling quantum dice with a superconducting qubit

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Abstract

One of the key challenges in quantum information is coherently manipulating the quantum state. However, it is an outstanding question whether control can be realized with low error. Only gates from the Clifford group -- containing $\pi$, $\pi/2$, and Hadamard gates -- have been characterized with high accuracy. Here, we show how the Platonic solids enable implementing and characterizing larger gate sets. We find that all gates can be implemented with low error. The results fundamentally imply arbitrary manipulation of the quantum state can be realized with high precision, providing new practical possibilities for designing efficient quantum algorithms.

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R. Barends, J. Kelly, A. Veitia, A. Megrant, A. G. Fowler, B. Campbell, Y. Chen, Z. Chen, B. Chiaro, A. Dunsworth, I. -C. Hoi, E. Jeffrey, C. Neill, P. J. J. O'Malley, J. Mutus, C. Quintana, P. Roushan, D. Sank, J. Wenner, T. C. White, A. N. Korotkov, A. N. Cleland, John M. Martinis. 2014-06-12. Rolling quantum dice with a superconducting qubit. https://doi.org/10.1103/physreva.90.030303

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