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Quantum nondemolition measurements of a qubit

D. V. Averin
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Abstract

The concept of quantum nondemolition (QND) measurement is extended to coherent oscillations in an individual two-state system. Such a measurement enables direct observation of intrinsic spectrum of these oscillations avoiding the detector-induced dephasing that affects the standard (non-QND) measurements. The suggested scheme can be realized in Josephson-junction qubits which combine flux and charge dynamics.

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D. V. Averin. 2002-02-06. Quantum nondemolition measurements of a qubit. https://doi.org/10.1103/physrevlett.88.207901

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