Charge Qubit Coupled to an Intense Microwave Electromagnetic Field in a Superconducting Nb Device: Evidence for Photon-Assisted Quasiparticle Tunneling
Journal article, 2013

We study a superconducting charge qubit coupled to an intensive electromagnetic field and probe changes in the resonance frequency of the formed dressed states. At large driving strengths, exceeding the qubit energy-level splitting, this reveals the well known Landau-Zener-Stückelberg interference structure of a longitudinally driven two-level system. For even stronger drives, we observe a significant change in the Landau-Zener-Stückelberg pattern and contrast. We attribute this to photon-assisted quasiparticle tunneling in the qubit. This results in the recovery of the qubit parity, eliminating effects of quasiparticle poisoning, and leads to an enhanced interferometric response. The interference pattern becomes robust to quasiparticle poisoning and has a good potential for accurate charge sensing.

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ARTIFICIAL-ATOM

Author

Sebastian Erik de Graaf

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Juha Leppäkangas

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

Astghik Adamyan

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Andrey Danilov

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Tobias Lindström

National Physical Laboratory (NPL)

Mikael Fogelström

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

Thilo Bauch

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Göran Johansson

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

Sergey Kubatkin

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Physical Review Letters

0031-9007 (ISSN) 1079-7114 (eISSN)

Vol. 111 13 Art. no. 137002- 137002

ELectric Field control Over Spin molecules (ELFOS)

European Commission (FP7), 2011-01-01 -- 2014-02-28.

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Infrastructure

Nanofabrication Laboratory

Subject Categories

Condensed Matter Physics

DOI

10.1103/PhysRevLett.111.137002

More information

Latest update

5/29/2018