Fluctuations of Energy-Relaxation Times in Superconducting Qubits

Jimmy Chen
Anthony Megrant
Rami Barends
Kunal Arya
Ben Chiaro
Yu Chen
Andrew Dunsworth
Brooks Foxen
Rob Graff
Trent Huang
Josh Mutus
Charles Neill
Amit Vainsencher
Jim Wenner
Vadim Smelyanskiy
John Martinis
Physical Review Letters, 121 (2018), pp. 090502

Abstract

Superconducting qubits are an attractive platform for quantum computing since they have demonstrated high-fidelity quantum gates and extensibility to modest system sizes. Nonetheless, an outstanding challenge is stabilizing their energy-relaxation times, which can fluctuate unpredictably in frequency and time. Here, we use qubits as spectral and temporal probes of individual two-level-system defects to provide direct evidence that they are responsible for the largest fluctuations. This research lays the foundation for stabilizing qubit performance through calibration, design and fabrication.

Research Areas