Interference and complementarity for two-photon hybrid entangled states

TL;DR

This paper reports the creation and analysis of two-photon hybrid entangled states, exploring their interference properties and the complementarity between single- and two-photon interference visibilities.

Contribution

It introduces a method to generate hybrid entangled states combining polarization and spatial degrees of freedom, and studies their interference and complementarity properties.

Findings

Demonstrated generation of hybrid entangled states via parametric down-conversion.

Analyzed the complementarity relation between one- and two-photon interference visibilities.

Explored the impact of birefringent double-slit on entanglement and interference patterns.

Abstract

In this work we generate two-photon hybrid entangled states (HES), where the polarization of one photon is entangled with the transverse spatial degree of freedom of the second photon. The photon pair is created by parametric down-conversion in a polarization-entangled state. A birefringent double-slit couples the polarization and spatial degrees of freedom of these photons and finally, suitable spatial and polarization projections generate the HES. We investigate some interesting aspects of the two-photon hybrid interference, and present this study in the context of the complementarity relation that exists between the visibilities of the one- and two-photon interference patterns.