Quantum-enhanced measurements without entanglement

  title={Quantum-enhanced measurements without entanglement},
  author={Daniel Braun and Gerardo Adesso and Fabio Benatti and Roberto Floreanini and Ugo Marzolino and Morgan W. Mitchell and Stefano Pirandola},
  journal={Reviews of Modern Physics},
Quantum-enhanced measurements exploit quantum mechanical effects for increasing the sensitivity of measurements of certain physical parameters and have great potential for both fundamental science and concrete applications. Most of the research has so far focused on using highly entangled states, which are, however, difficult to produce and to stabilize for a large number of constituents. In the following we review alternative mechanisms, notably the use of more general quantum correlations… 

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