General framework for estimating the ultimate precision limit in noisy quantum-enhanced metrology

  title={General framework for estimating the ultimate precision limit in noisy quantum-enhanced metrology},
  author={Beate I. Escher and Ruynet. L. de Matos Filho and L. Davidovich},
  journal={Nature Physics},
Quantum strategies can help to make parameter-estimation schemes more precise, but for noisy processes it is typically not known how large that improvement may be. Here, a universal quantum bound is derived for the error in the estimation of parameters that characterize dynamical processes. 

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