Characterization of control in a superconducting qutrit using randomized benchmarking
Michal Kononenko, Muhammet Ali Yurtalan, S. Ren, Jiahao Shi, Sahel Ashhab, Adrian Lupaşcu · Physical Review Research · 2021
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 ± 0.05%.For a selected subset of the Clifford group, we perform quantum process tomography and observe the behavior 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 primarily to decoherence and have a significant contribution from level shifts.This work demonstrates high-fidelity qutrit control and outlines avenues for future work on the optimal control of superconducting qudits.