# On the observation of nonclassical excitations in Bose–Einstein condensates

@article{Finke2016OnTO, title={On the observation of nonclassical excitations in Bose–Einstein condensates}, author={Andreas Finke and Piyush Jain and Silke E. Ch. Weinfurtner}, journal={New Journal of Physics}, year={2016}, volume={18} }

In the recent experimental and theoretical literature well-established nonclassicality criteria from the field of quantum optics have been directly applied to the case of excitations in matter-waves. Among these are violations of Cauchy–Schwarz inequalities, Glauber–Sudarshan P-nonclassicality, sub-Poissonian number-difference squeezing (also known as the two-mode variance) and the criterion of nonseparability. We review the strong connection of these criteria and their meaning in quantum…

## 19 Citations

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