Quantum estimation via parametric amplification in circuit-QED arrays
Ashley Wilkins, Carlos Sabín · Physical Review A · 2015
We propose a scheme for quantum estimation by means of parametric amplification in circuit quantum electrodynamics. The modulation of a superconducting quantum interference device 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 (QFI). To achieve a large number of independent measurements we propose using an array of noninteracting resonators. We show that the combination of both large QFI and a large number of measurements enables, in principle, the use of this setup for quantum metrology applications.