Randomized Benchmarking and Process Tomography for Gate Errors in a Solid-State Qubit
Jerry M. Chow, Jay Gambetta, Lars Tornberg, Jens Koch, Lev S. Bishop, Andrew Houck, Blake Johnson, Luigi Frunzio, S. M. Girvin, R. J. Schoelkopf · Physical Review Letters · 2009
We present measurements of single-qubit gate errors for a superconducting qubit. Results from quantum process tomography and randomized benchmarking are compared with gate errors obtained from a double pi pulse experiment. Randomized benchmarking reveals a minimum average gate error of 1.1+/-0.3% and a simple exponential dependence of fidelity on the number of gates. It shows that the limits on gate fidelity are primarily imposed by qubit decoherence, in agreement with theory.