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arXiv · 1509.04142

Quantum estimation via parametric amplification in circuit QED arrays

Ashley Wilkins·Carlos Sabín
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Abstract

We propose a scheme for quantum estimation by means of parametric amplification in circuit Quantum Electrodynamics. The modulation of a SQUID interrupting a superconducting waveguide transforms an initial thermal two-mode squeezed state in such a way that the new state is sensitive to the features of the parametric amplifier. We find the optimal initial parameters which maximize the Quantum Fisher Information. In order to achieve a large number of independent measurements we propose to use an array of non-interacting resonators. We show that the combination of both large QFI and large number of measurements enables -in principle- the use of this setup for Quantum Metrology applications.

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Ashley Wilkins, Carlos Sabín. 2015-12-14. Quantum estimation via parametric amplification in circuit QED arrays. https://doi.org/10.1103/physreva.92.062102

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