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arXiv · 2009.00599

Characterization of Control in a Superconducting Qutrit Using Randomized Benchmarking

M. Kononenko·M. A. Yurtalan·S. Ren·J. Shi·S. Ashhab·A. Lupascu
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Abstract

We characterize control of a qutrit implemented in the lowest three energy levels of a capacitively-shunted flux-biased superconducting circuit. Randomized benchmarking over the qutrit Clifford group yields an average fidelity of 98.89 $\pm$ 0.05%. For a selected subset of the Clifford group, we perform quantum process tomography and observe the behaviour of repeated gate sequences. Each qutrit gate is generated using only two-state rotations via a method applicable to any unitary. We find that errors are due to decoherence primarily and have a significant contribution from level shifts. This work demonstrates high-fidelity qutrit control and outlines avenues for future work on optimal control of superconducting qudits.

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M. Kononenko, M. A. Yurtalan, S. Ren, J. Shi, S. Ashhab, A. Lupascu. 2020-09-01. Characterization of Control in a Superconducting Qutrit Using Randomized Benchmarking. https://doi.org/10.1103/physrevresearch.3.l042007

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