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arXiv · 2004.06412

Quantifying entanglement of parametric down-converted states in all degrees of freedom

Filippus S. Roux
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Abstract

The amount of entanglement that exists in a parametric down-converted state is investigated in terms of all the degrees of freedom of the state. We quantify the amount of entanglement by the Schmidt number of the state, represented as a pure bipartite state by tagging the down-converted photons in terms of orthogonal states of polarization with the aid of type II phase-matching. To facilitate our calculations, we use a Wigner functional approach, which allows the incorporation of the full infinite dimensional spatiotemporal degrees of freedom. A quantitative example with reasonably achievable experimental conditions is considered to demonstrate that extremely large Schmidt numbers are achievable.

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BibTeXRIS

Filippus S. Roux. 2020-04-14. Quantifying entanglement of parametric down-converted states in all degrees of freedom. https://doi.org/10.1103/physrevresearch.2.023137

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