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Quadratic Quantum Measurements

Wenjin Mao·Dmitri V. Averin·Rusko Ruskov·Alexander N. Korotkov
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Abstract

We develop a theory of quadratic quantum measurements by a mesoscopic detector. It is shown that quadratic measurements should have non-trivial quantum information properties, providing, for instance, a simple way of entangling two non-interacting qubits. We also calculate output spectrum of a quantum detector with both linear and quadratic response continuously monitoring coherent oscillations in two qubits.

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Wenjin Mao, Dmitri V. Averin, Rusko Ruskov, Alexander N. Korotkov. 2004-01-24. Quadratic Quantum Measurements. https://doi.org/10.1103/physrevlett.93.056803

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