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Efficient Quantum State Estimation by Continuous Weak Measurement and Dynamical Control

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 نشر من قبل Poul S. Jessen
 تاريخ النشر 2006
  مجال البحث فيزياء
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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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