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Bounds on Quantum Multiple-Parameter Estimation with Gaussian State

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 نشر من قبل Yang Gao
 تاريخ النشر 2014
  مجال البحث فيزياء
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We investigate the quantum Cramer-Rao bounds on the joint multiple-parameter estimation with the Gaussian state as a probe. We derive the explicit right logarithmic derivative and symmetric logarithmic derivative operators in such a situation. We compute the corresponding quantum Fisher information matrices, and find that they can be fully expressed in terms of the mean displacement and covariance matrix of the Gaussian state. Finally, we give some examples to show the utility of our analytical results.



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