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Efficient Quantum State Estimation by Continuous Weak Measurement and Dynamical Control

Greg A. Smith·Andrew Silberfarb·Ivan H. Deutsch·Poul S. Jessen
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Abstract

We demonstrate a fast, robust and non-destructive protocol for quantum state estimation based on continuous weak measurement in the presence of a controlled dynamical evolution. Our experiment uses optically probed atomic spins as a testbed, and successfully reconstructs a range of trial states with fidelities of ~90%. The procedure holds promise as a practical diagnostic tool for the study of complex quantum dynamics, the testing of quantum hardware, and as a starting point for new types of quantum feedback control.

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Greg A. Smith, Andrew Silberfarb, Ivan H. Deutsch, Poul S. Jessen. 2006-06-13. Efficient Quantum State Estimation by Continuous Weak Measurement and Dynamical Control. https://doi.org/10.1103/physrevlett.97.180403

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