Parity switching in a full-shell superconductor-semiconductor nanowire qubit

Abstract

The rate of charge-parity switching in a full-shell superconductor-semiconductor nanowire qubit is measured by directly monitoring the dispersive shift of a readout resonator. At zero magnetic field, the measured switching time scale TP is on the order of 100ms. Two-tone spectroscopy data post-selected on charge parity is demonstrated. With increasing temperature or magnetic field, TP is at first constant, then exponentially suppressed, consistent with a model that includes both nonequilibrium and thermally activated quasiparticles. As TP is suppressed, qubit lifetime T1 also decreases. The long TP∼0.1s at zero field is promising for future development of qubits based on hybrid nanowires.