One- and two-photon spectroscopy of a flux qubit coupled to a microscopic defect

Article

关键词: PERSISTENT-CURRENT QUBIT;    SUPERCONDUCTING QUBIT;    2-LEVEL SYSTEM;    QUANTUM;   

DOI  :  10.1103/PhysRevB.80.172506

来源: SCIE

【 摘 要 】

We observed the dynamics of a superconducting flux qubit coupled to an extrinsic quantum system (EQS). The presence of the EQS is revealed by an anticrossing in the spectroscopy of the qubit. The excitation of a two-photon transition to the third excited state of the qubit-EQS system allows us to extract detailed information about the energy-level structure and the coupling of the EQS. We deduce that the EQS is a two-level system, with a transverse coupling to the qubit. The transition frequency and the coupling of the EQS changed during experiments, which supports the idea that the EQS is a two-level system of microscopic origin.

【 授权许可】

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