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arXiv · 1504.04002

Fast quantum non-demolition readout from longitudinal qubit-oscillator interaction

Nicolas Didier·Jérôme Bourassa·Alexandre Blais
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Abstract

We show how to realize high-fidelity quantum non-demolition qubit readout using longitudinal qubit-oscillator interaction. This is realized by modulating the longitudinal coupling at the cavity frequency. The qubit-oscillator interaction then acts as a qubit-state dependent drive on the cavity, a situation that is fundamentally different from the standard dispersive case. Single-mode squeezing can be exploited to exponentially increase the signal-to-noise ratio of this readout protocol. We present an implementation of this idea in circuit quantum electrodynamics and a possible multi-qubit architecture.

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Nicolas Didier, Jérôme Bourassa, Alexandre Blais. 2015-04-15. Fast quantum non-demolition readout from longitudinal qubit-oscillator interaction. https://doi.org/10.1103/physrevlett.115.203601

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