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arXiv · 0807.0797

Landau-Zener Transitions in an Adiabatic Quantum Computer

J. Johansson·M. H. S. Amin·A. J. Berkley·P. Bunyk·V. Choi·R. Harris·M. W. Johnson·T. M. Lanting·Seth Lloyd·G. Rose
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Abstract

We report an experimental measurement of Landau-Zener transitions on an individual flux qubit within a multi-qubit superconducting chip designed for adiabatic quantum computation. The method used isolates a single qubit, tunes its tunneling amplitude Delta into the limit where Delta is much less than both the temperature T and the decoherence-induced energy level broadening, and forces it to undergo a Landau-Zener transition. We find that the behavior of the qubit agrees to a high degree of accuracy with theoretical predictions for Landau-Zener transition probabilities for a double-well quantum system coupled to 1/f magnetic flux noise.

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J. Johansson, M. H. S. Amin, A. J. Berkley, P. Bunyk, V. Choi, R. Harris, M. W. Johnson, T. M. Lanting, Seth Lloyd, G. Rose. 2008-07-04. Landau-Zener Transitions in an Adiabatic Quantum Computer. https://doi.org/10.1103/physrevb.80.012507

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