Detection of a persistent-current qubit by resonant activation

P. Bertet; I. Chiorescu; K. Semba; C. J. P. M Harmans; J. E. Mooij

doi:10.1103/physrevb.70.100501

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Detection of a persistent-current qubit by resonant activation

P. Bertet·I. Chiorescu·K. Semba·C. J. P. M Harmans·J. E. Mooij

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Abstract

We present the implementation of a new scheme to detect the quantum state of a persistent-current qubit. It relies on the dependency of the measuring Superconducting Quantum Interference Device (SQUID) plasma frequency on the qubit state, which we detect by resonant activation. With a measurement pulse of only 5ns, we observed Rabi oscillations with high visibility (65%).

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P. Bertet, I. Chiorescu, K. Semba, C. J. P. M Harmans, J. E. Mooij. 2004-05-03. Detection of a persistent-current qubit by resonant activation. https://doi.org/10.1103/physrevb.70.100501

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