Quantum interference and non-locality of independent photons from disparate sources

TL;DR

This paper explores the non-classical and non-local properties of mixed quantum and semi-quantum photon sources, including photon added thermal and coherent sources, by analyzing photon-photon correlations and inequality violations.

Contribution

It provides a quantitative analysis of non-classicality and non-locality in a new class of mixed photon sources at the quantum-classical boundary, including experimental relevance.

Findings

Violations of Cauchy-Schwarz inequality demonstrate nonclassicality.

Bell-type inequalities are violated, indicating non-locality.

Explicit results on photon-photon correlation visibility are presented.

Abstract

We quantitatively investigate the non-classicality and non-locality of a whole new class of mixed disparate quantum and semiquantum photon sources at the quantum-classical boundary. The latter include photon added thermal and photon added coherent sources, experimentally investigated recently by Zavatta et al. [Phys. Rev. Lett. 103, 140406 (2009)]. The key quantity in our investigations is the visibility of the corresponding photon-photon correlation function. We present explicit results on the violations of the Cauchy-Schwarz inequality - which is a measure of nonclassicality - as well as of Bell-type inequalities.