2022/11/28 by Mathias Pont, Pont, Mathias, Giacomo Corrielli +43 · 1 voice · 1 citation
Computer Science · Physics and Astronomy · #FOS: Physical sciences #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Physics (quant-ph) #Quantum optics and atomic interactions #quant-ph
paper · pdf · doi:10.48550/arxiv.2211.15626
openalex publication_date 2022/11/28 · arxiv published 2022/11/28 · arxiv updated 2022/11/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Mutually entangled multi-photon states are at the heart of all-optical quantum technologies. While impressive progresses have been reported in the generation of such quantum light states using free space apparatus, high-fidelity high-rate on-chip entanglement generation is crucial for future scalability. In this work, we use a bright quantum-dot based single-photon source to demonstrate the high fidelity generation of 4-photon Greenberg-Horne-Zeilinger (GHZ) states with a low-loss reconfigurable glass photonic circuit. We reconstruct the density matrix of the generated states using full quantum-state tomography reaching an experimental fidelity to the target |GHZ4⟩ of FGHZ4 (86.0±0.4) %, and a purity of PGHZ4=(76.3±0.6) %. The entanglement of the generated states is certified with a semi device-independent approach through the violation of a Bell-like inequality by more than 39 standard deviations. Finally, we carry out a four-partite quantum secret sharing protocol on-chip where a regulator shares with three interlocutors a sifted key with up to 1978 bits, achieving a qubit-error rate of 10.87 %. These results establish that the quantum-dot technology combined with glass photonic circuitry for entanglement generation on chip offers a viable path for intermediate scale quantum computation and communication.