Characterizing decoherence rates of a superconducting qubit by direct microwave scattering
Journal article, 2021
We experimentally investigate a superconducting qubit coupled to the end of an open transmission line, in a regime where the qubit decay rates to the transmission line and to its own environment are comparable. We perform measurements of coherent and incoherent scattering, on- and off-resonant fluorescence, and time-resolved dynamics to determine the decay and decoherence rates of the qubit. In particular, these measurements let us discriminate between non-radiative decay and pure dephasing. We combine and contrast results across all methods and find consistent values for the extracted rates. The results show that the pure dephasing rate is one order of magnitude smaller than the non-radiative decay rate for our qubit. Our results indicate a pathway to benchmark decoherence rates of superconducting qubits in a resonator-free setting.
Author
Yong Lu
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology
Andreas Bengtsson
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology
Jonathan Burnett
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology
National Physical Laboratory (NPL)
Emely Wiegand
Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics
Baladitya Suri
Indian Institute of Science
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology
Philip Krantz
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Anita Fadavi Roudsari
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology
Anton Frisk Kockum
Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics
Simone Gasparinetti
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology
Göran Johansson
Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics
Per Delsing
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology
npj Quantum Information
20566387 (eISSN)
Vol. 7 1 35Subject Categories
Telecommunications
Atom and Molecular Physics and Optics
Other Physics Topics
DOI
10.1038/s41534-021-00367-5