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arXiv · 1502.00607

Heisenberg-limited qubit readout with two-mode squeezed light

Nicolas Didier·Archana Kamal·William D. Oliver·Alexandre Blais·Aashish A. Clerk
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Abstract

We show how to use two-mode squeezed light to exponentially enhance cavity-based dispersive qubit measurement. Our scheme enables true Heisenberg-limited scaling of the measurement, and crucially, is not restricted to small dispersive couplings or unrealistically long measurement times. It involves coupling a qubit dispersively to two cavities, and making use of a symmetry in the dynamics of joint cavity quadratures (a so-called quantum-mechanics-free subsystem). We discuss the basic scaling of the scheme and its robustness against imperfections, as well as a realistic implementation in circuit quantum electrodynamics.

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Nicolas Didier, Archana Kamal, William D. Oliver, Alexandre Blais, Aashish A. Clerk. 2015-02-02. Heisenberg-limited qubit readout with two-mode squeezed light. https://doi.org/10.1103/physrevlett.115.093604

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