2015/04/15 by Nicolas Didier, Jérôme Bourassa, Alexandre Blais · 1 citation
Physics and Astronomy · #quant-ph #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevlett.115.203601
published as Phys. Rev. Lett. 115, 203601 (2015) · 5 pages, 3 figures, Supplemental Material
arxiv created 2015/04/15 · arxiv updated 2015/11/18
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.