Full-mode Characterisation of Correlated Photon Pairs Generated in Spontaneous Downconversion

Abstract

Spontaneous parametric downconversion is the primary source to generate entangled photon pairs in quantum photonics laboratories. Depending on the experimental design, the generated photon pairs can be correlated in the frequency spectrum, polarisation, position-momentum, and spatial modes. Exploring the spatial modes' correlation has hitherto been limited to the polar coordinates' azimuthal angle, and a few attempts to study Walsh modes radial states. Here, we study the full-mode correlation, on a Laguerre-Gauss basis, between photon pairs generated in a type-I crystal. Furthermore, we explore the effect of a structured pump beam possessing different spatial modes onto bi-photon spatial correlation. Finally, we use the capability to project over arbitrary spatial mode superpositions to perform the bi-photon state's full quantum tomography in a 16-dimensional subspace.

10 Pages,7 Figures, to be submitted

References in corpus (2)

• Full-field quantum correlations of spatially entangled photons
• Radial coherent and intelligent states of paraxial wave equation

Cited by in corpus (7)

• Entanglement-Based Quantum Information Technology
• Conformal frequency conversion for arbitrary vectorial structured light
• Biphoton State Reconstruction via Phase Retrieval Methods
• Conservation of angular momentum on a single-photon level
• Spectral Properties of Transverse Laguerre-Gauss Modes in Parametric Down-Conversion
• Schmidt modes carrying orbital angular momentum generated by cascaded systems pumped with Laguerre-Gaussian beams
• Entangled ripples and twists of light: Radial and azimuthal Laguerre-Gaussian mode entanglement