2025/09/02 by Baghdasar Baghdasaryan, Kaushik Joarder, Baghdasaryan, Baghdasar +3
Computer Science · Physics and Astronomy · #Beam splitter #Detector #Geometrical optics #Laser beams #Light beam #Mechanical and Optical Resonators #Nonlinear optics #Photon #Photonics #Physical optics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum entanglement #Quantum information science #Quantum network #Quantum optics #Quantum optics and atomic interactions #Repeater (horology) #Topology (electrical circuits) #Wavefront
paper · pdf · doi:10.1364/oe.592481
openalex publication_date 2026/06/17 · openalex created_date 2026/06/18 · openalex updated_date 2026/07/21
Entanglement swapping is a fundamental building block for realizing first-generation quantum repeaters, which are essential for building global quantum networks. Current quantum repeater systems still struggle to achieve practical communication rates. High-dimensional (HD) encoding can significantly improve repeater efficiency by boosting information capacity and enhancing noise tolerance and security. However, the experimental demonstration of this protocol so far has been limited only to two-dimensional systems due to the requirement of strong nonlinear interactions. Here, we theoretically show that a modular linear-optics setup can implement HD entanglement swapping based on ancillary photons. For a four-dimensional scenario, we present an experimental design that employs hyper-entanglement in the polarization and time-bin degrees of freedom. This setup resolves the most challenging part of the ancillary photons-based approach, namely the necessary preparation of the ancilla state and the analysis of the resulting swapped state.