Freiburg 2019 – wissenschaftliches Programm
FM 39.4: Talk
Dienstag, 24. September 2019, 15:00–15:15, 3044
Photon-assisted charge-parity jumps in a superconducting qubit — Manuel Houzet1, Kyle Serniak2, •Gianluigi Catelani3,4, Michel Devoret2, and Leonid Glazman2 — 1CEA, Grenoble, France — 2Depts. of Physics and Applied Physics, Yale University, New Haven, USA — 3JARA Institute for Quantum Information, Forschungszentrum Jülich, Germany — 4Yale Quantum Institute, Yale University, New Haven, USA
We evaluate the rates of energy and phase relaxation of a superconducting qubit caused by stray photons with energy exceeding the threshold for breaking a Cooper pair. All channels of relaxation within this mechanism are associated with the change in the charge parity of the qubit, enabling the separation of the photon-assisted processes from other contributions to the relaxation rates. Among the signatures of the new mechanism is the same order of rates of the transitions in which a qubit loses or gains energy. Our theory offers a natural explanation of recent measurements.