English

Violation of the Cauchy-Schwarz inequality with matter waves

Quantum Physics 2012-06-28 v3 Quantum Gases

Abstract

The Cauchy-Schwarz (CS) inequality -- one of the most widely used and important inequalities in mathematics -- can be formulated as an upper bound to the strength of correlations between classically fluctuating quantities. Quantum mechanical correlations can, however, exceed classical bounds.Here we realize four-wave mixing of atomic matter waves using colliding Bose-Einstein condensates, and demonstrate the violation of a multimode CS inequality for atom number correlations in opposite zones of the collision halo. The correlated atoms have large spatial separations and therefore open new opportunities for extending fundamental quantum-nonlocality tests to ensembles of massive particles.

Keywords

Cite

@article{arxiv.1204.0058,
  title  = {Violation of the Cauchy-Schwarz inequality with matter waves},
  author = {K. V. Kheruntsyan and J. -C. Jaskula and P. Deuar and M. Bonneau and G. B. Partridge and J. Ruaudel and R. Lopes and D. Boiron and C. I. Westbrook},
  journal= {arXiv preprint arXiv:1204.0058},
  year   = {2012}
}

Comments

Final published version (with minor changes). 5 pages, 3 figures, plus Supplementary Material