Quantum metrology with nonclassical states of atomic ensembles

  title={Quantum metrology with nonclassical states of atomic ensembles},
  author={Luca Pezz{\`e} and Augusto Smerzi and Markus K. Oberthaler and Roman Schmied and Philipp Treutlein},
  journal={Reviews of Modern Physics},
Quantum technologies exploit entanglement to revolutionize computing, measurements, and communications. This has stimulated the research in different areas of physics to engineer and manipulate fragile many-particle entangled states. Progress has been particularly rapid for atoms. Thanks to the large and tunable nonlinearities and the well-developed techniques for trapping, controlling, and counting, many groundbreaking experiments have demonstrated the generation of entangled states of trapped… 
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