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arXiv · 1312.1319

Implementing generalized measurements with superconducting qubits

Justin Dressel·Todd A. Brun·Alexander N. Korotkov
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Abstract

We describe a method to perform any generalized purity-preserving measurement of a qubit with techniques tailored to superconducting systems. First, we consider two methods for realizing a two-outcome partial projection: using a thresholded continuous measurement in the circuit QED setup, or using an indirect ancilla qubit measurement. Second, we decompose an arbitrary purity-preserving two-outcome measurement into single qubit unitary rotations and a partial projection. Third, we systematically reduce any multiple-outcome measurement to a sequence of such two-outcome measurements and unitary operations. Finally, we consider how to define suitable fidelity measures for multiple-outcome generalized measurements.

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Justin Dressel, Todd A. Brun, Alexander N. Korotkov. 2014-07-15. Implementing generalized measurements with superconducting qubits. https://doi.org/10.1103/physreva.90.032302

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