English

Direct Sampling of Negative Quasiprobabilities of a Squeezed State

Quantum Physics 2011-09-12 v2

Abstract

Although squeezed states are nonclassical states, so far, their nonclassicality could not be demonstrated by negative quasiprobabilities. In this work we derive pattern functions for the direct experimental determination of so-called nonclassicality quasiprobabilities. The negativities of these quantities turn out to be necessary and sufficient for the nonclassicality of an arbitrary quantum state and are therefore suitable for a direct and general test of nonclassicality. We apply the method to a squeezed vacuum state of light that was generated by parametric down-conversion in a second-order nonlinear crystal.

Keywords

Cite

@article{arxiv.1105.4591,
  title  = {Direct Sampling of Negative Quasiprobabilities of a Squeezed State},
  author = {T. Kiesel and W. Vogel and B. Hage and R. Schnabel},
  journal= {arXiv preprint arXiv:1105.4591},
  year   = {2011}
}

Comments

4 pages, 4 figures, supplementary material added

R2 v1 2026-06-21T18:11:22.768Z