Mainz 2026 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
Q: Fachverband Quantenoptik und Photonik
Q 56: Quantum Optics and Control I
Q 56.3: Talk
Thursday, March 5, 2026, 15:15–15:30, P 3
Towards generalized pump beam engineering for maximal entanglement in Laguerre-Gaussian modes — •Richard Bernecker1,2, Baghdasar Baghdasaryan3, and Stephan Fritzsche1,2 — 1Institute for Theoretical Physics, Friedrich Schiller University Jena, Fröbelstieg 1, 07743 Jena, Germany — 2Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena, Germany — 3Institute of Applied Physics, Friedrich Schiller University Jena, Albert-Einstein-Str. 6, 07745 Jena, Germany
The spatial entanglement of photons in Laguerre-Gaussian (LG) modes has proven to be a powerful resource for high-dimensional quantum information processing. LG modes are indexed by a radial number p and an azimuthal number ℓ, the latter being associated with orbital angular momentum (OAM). While most studies over the past decades have focused on the OAM, recent advances now enable full-mode characterization, including the radial index p. However, no general strategy exists to generate specific high-dimensional target states in the full LG basis.
In this contribution, we present a generalized approach to spatial pump-beam engineering that enables the generation of maximally entangled states (MESs) from spontaneous parametric down-conversion. MESs constitute the high-dimensional analogue of Bell states and form ideal resources for quantum information tasks. We show that a tailored superposition of LG pump modes, combined with an optimized choice of the detection subspace, allows for the controlled engineering of MESs across both radial and azimuthal mode indices.
Keywords: High-dimensional entanglement; Laguerre-Gaussian modes; Orbital angular momentum; Photon pairs; Spontaneous parametric down-conversion