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Nondestructive readout for a superconducting flux qubit

A. Lupascu·C. J. M. Verwijs·R. N. Schouten·C. J. P. M. Harmans·J. E. Mooij
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Abstract

We present a new readout method for a superconducting flux qubit, based on the measurement of the Josephson inductance of a superconducting quantum interference device that is inductively coupled to the qubit. The intrinsic flux detection efficiency and back-action are suitable for a fast and nondestructive determination of the quantum state of the qubit, as needed for readout of multiple qubits in a quantum computer. We performed spectroscopy of a flux qubit and we measured relaxation times of the order of 80 $μs$.

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A. Lupascu, C. J. M. Verwijs, R. N. Schouten, C. J. P. M. Harmans, J. E. Mooij. 2004-10-28. Nondestructive readout for a superconducting flux qubit. https://doi.org/10.1103/physrevlett.93.177006

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