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arXiv · 0908.0541

Testing quantum nonlocality by generalized quasiprobability functions

Seung-Woo Lee·Hyunseok Jeong·Dieter Jaksch
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Abstract

We derive a Bell inequality based on a generalized quasiprobability function which is parameterized by one non-positive real value. Two types of known Bell inequalities formulated in terms of the Wigner and Q functions are included as limiting cases. We investigate violations of our Bell inequalities for single photon entangled states and two-mode squeezed vacuum states when varying the detector efficiency. We show that the Bell inequality for the Q function allows the lowest detection efficiency for violations of local realism.

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Seung-Woo Lee, Hyunseok Jeong, Dieter Jaksch. 2009-08-04. Testing quantum nonlocality by generalized quasiprobability functions. https://doi.org/10.1103/physreva.80.022104

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