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Spectroscopy of three strongly coupled flux qubits

A. O. Niskanen·K. Harrabi·F. Yoshihara·Y. Nakamura·J. S. Tsai
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Abstract

We have carried out spectroscopic measurements of a system of three strongly coupled four-junction flux qubits. The samples studied cover a wide range of parameters with the coupling energy between neighboring qubits varying between 0.75 GHz and 6.05 GHz. The observed complicated spectra agree well with eight-level theory. The experiments are relevant for the realization of a tunable coupling between qubits.

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A. O. Niskanen, K. Harrabi, F. Yoshihara, Y. Nakamura, J. S. Tsai. 2006-09-25. Spectroscopy of three strongly coupled flux qubits. https://doi.org/10.1103/physrevb.74.220503

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