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Flux Qubits and Readout Device with Two Independent Flux Lines

B. L. T. Plourde·T. L. Robertson·P. A. Reichardt·T. Hime·S. Linzen·C. -E. Wu·John Clarke
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Abstract

We report measurements on two superconducting flux qubits coupled to a readout Superconducting QUantum Interference Device (SQUID). Two on-chip flux bias lines allow independent flux control of any two of the three elements, as illustrated by a two-dimensional qubit flux map. The application of microwaves yields a frequency-flux dispersion curve for 1- and 2-photon driving of the single-qubit excited state, and coherent manipulation of the single-qubit state results in Rabi oscillations and Ramsey fringes. This architecture should be scalable to many qubits and SQUIDs on a single chip.

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B. L. T. Plourde, T. L. Robertson, P. A. Reichardt, T. Hime, S. Linzen, C. -E. Wu, John Clarke. 2005-01-29. Flux Qubits and Readout Device with Two Independent Flux Lines. https://doi.org/10.1103/physrevb.72.060506

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