Researchers cut superconducting qubit errors with a preliminary measurement

Researchers at the University of Regensburg and international partners demonstrated a measurement method that reduced a superconducting qubit's average error rate from approximately 0.14% to 0.065%. The experiment, published in Applied Physics Reviews, used hardware at the Israeli Quantum Computing Center. The qubit's operating frequency switched between two known values because of material defects. An additional measurement identified the active frequency before quantum operations, allowing control signals to be adjusted in real time. The method requires frequencies that are known beforehand and sufficiently distinct. Each frequency must also remain stable long enough for the adjusted signals to work.