Omar Calderón | Searcharxiv

arXiv2018

Correlation control for pure and efficiently generated heralded single photons

We present a detailed study on the properties of single photons generated by spontaneous parametric down conversion (SPDC) when both the spectral and spatial degrees of freedom are controlled by means of filters. Our results show that it is possible to obtain pure heralded single photons with high heralding efficiency despite the use of filters. Moreover, we report an asymmetry on the single photon properties exhibited in type-II SPDC sources that depends on choosing the signal or the idler photon as the heralding one.

quant-ph↗

arXiv2016

Experimental verification of a quantumness criterion for single systems based on a Bell-like inequality

In this letter, we propose and experimentally test a quantumness criterion for single systems. The criterion is based on the violation of an already reported classical inequality. This inequality is expressed in terms of joint probabilities that we identify as realizations of preparation-and-measurement schemes. Our analysis points out that superposition is the key notion to grasp the quantum nature of physical systems. We verify our criterion in an all-optical experimental setup with heralded single photons generated via spontaneous parametric down conversion and use exclusively projective preparations and projective measurements.

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