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arXiv · 1510.08214

Realization of a binary-outcome projection measurement of a three-level superconducting quantum system

Markus Jerger·Pascal Macha·Andrés Rosario Hamann·Yarema Reshitnyk·Kristinn Juliusson·Arkady Fedorov
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Abstract

Binary-outcome measurements allow to determine whether a multi-level quantum system is in a certain state while preserving quantum coherence between all orthogonal states. In this paper, we explore different regimes of the dispersive readout of a three-level superconducting quantum system coupled to a microwave cavity in order to implement binary-outcome measurements. By designing identical cavity frequency shifts for the first and second excited states of the system, we realize strong projective binary-outcome measurements onto its ground state with a fidelity of $94.3\%$. Complemented with standard microwave control and low-noise parametric amplification, this scheme enables the quantum non-demolition detection of leakage errors and can be used to create sets of compatible measurements to reveal the contextual nature of superconducting circuits.

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Markus Jerger, Pascal Macha, Andrés Rosario Hamann, Yarema Reshitnyk, Kristinn Juliusson, Arkady Fedorov. 2016-08-18. Realization of a binary-outcome projection measurement of a three-level superconducting quantum system. https://doi.org/10.1103/physrevapplied.6.014014

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