Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Conference on Lasers and Electro-Optics

Spatial Multiplexing of Atom-Photon Entanglement Sources

Zhongxiao Xu, Long Tian, Shujing Li, Hai Wang

Published Jan 1, 2018• 0 citations
Publisher

Abstract

We build a multiplexed light-matter interface and then demonstrate a ~sixfold (~fourfold) probability increase in generating entangled atom-photon (photon-photon) pairs. The measured compositive Bell parameter for the multiplexed interface is 2.49±0.03 combined with a memory lifetime of up to ~51 μs.
DOI
10.1364/cleo_qels.2018.fm4h.5

Related papers

Spatial Multiplexing of Atom-Photon Entanglement Sources using Feedforward Control and Switching Networks

Long Tian, Zhongxiao Xu, Lirong Chen +6 more

The light-matter quantum interface that can create quantum correlations or entanglement between a photon and one atomic collective excitation is a fundamental building block for a quantum repeater. The intrinsic limit is that the probability of preparing such nonclassical atom-photon correlations has to be kept low in order to suppress multiexcitation. To enhance this probability without introducing multiexcitation errors, a promising scheme is to apply multimode memories to the interface. Significant progress has been made in temporal, spectral, and spatial multiplexing memories, but the enhanced probability for generating the entangled atom-photon pair has not been experimentally realized. Here, by using six spin-wave-photon entanglement sources, a switching network, and feedforward control, we build a multiplexed light-matter interface and then demonstrate a ∼sixfold (∼fourfold) probability increase in generating entangled atom-photon (photon-photon) pairs. The measured compositive Bell parameter for the multiplexed interface is 2.49±0.03 combined with a memory lifetime of up to ∼51 μs.

arXiv:1610.02298•Physical Review Letters•Sep 29, 2017•46 citations

Multiplexed spin-wave–photon entanglement source using temporal multimode memories and feedforward-controlled readout

Yafei Wen, Pai Zhou, Zhongxiao Xu +6 more

A source that can generate atom-photon quantum correlations or entanglement based on a quantum memory is a basic building block of quantum repeaters (QRs). To achieve high entanglement generation rates in ensemble-based QRs, spatial-, temporal-, and spectral-multimode memories are needed. Previous temporal-multimode memories are based on rephasing mechanisms in inhomogeneously broadened media. Here, by applying a train of write pulses in time, with each pulse coming from a different direction, to a homogeneously broadened atomic ensemble to induce Duan-Lukin-Cirac-Zoller-like Raman processes, we prepare up to 19 pairs of modes, namely, one spin-wave mode and one photonic time bin. Spin-wave-photon (i.e., atom-photon) entanglement is probabilistically produced in these mode pairs. Based on the stored spin-wave modes together with feedforward-controlled readout, we build a temporally multiplexed source and then demonstrate an 18.8-fold increase in the probability of the generation of spin-wave-photon entanglement compared to the sources that use individual modes. The measured Bell parameter for the multiplexed source is $2.30\ifmmode\pm\else\textpm\fi{}0.02$, and the memory lifetime is 30 \ensuremath{\mu}s.

arXiv:1810.06143•Physical Review A•Jul 25, 2019•27 citations

Cavity-enhanced and temporally multiplexed atom-photon entanglement interface

Hailong Liu, Minjie Wang, Haole Jiao +4 more

Practical realization of quantum repeaters requires quantum memories with high retrieval efficiency, multi-mode storage capacities, and long lifetimes. Here, we report a high-retrieval-efficiency and temporally multiplexed atom-photon entanglement source. A train of 12 write pulses in time is applied to a cold atomic ensemble along different directions, which generates temporally multiplexed pairs of Stokes photons and spin waves via Duan-Lukin-Cirac-Zoller processes. The two arms of a polarization interferometer are used to encode photonic qubits of 12 Stokes temporal modes. The multiplexed spin-wave qubits, each of which is entangled with one Stokes qubit, are stored in a "clock" coherence. A ring cavity that resonates simultaneously with the two arms of the interferometer is used to enhance retrieval from the spin-wave qubits, with the intrinsic retrieval efficiency reaching 70.4%. The multiplexed source gives rise to a ∼12.1-fold increase in atom-photon entanglement-generation probability compared to the single-mode source. The measured Bell parameter for the multiplexed atom-photon entanglement is 2.21(2), along with a memory lifetime of up to ∼125 µs.

Optics Express•Jan 26, 2023•8 citations

Long-lived and multiplexed atom-photon entanglement interface with feed-forward-controlled readouts

Shengzhi Wang, Minjie Wang, Yafei Wen +4 more

Abstract Quantum interfaces (QIs) that generate entanglement between photonic and spin-wave (atomic memory) qubits are basic building block for quantum repeaters. Realizing ensemble-based repeaters in practice requires quantum memory providing long lifetimes and multimode capacity. Significant progress has been achieved on these separate goals. The remaining challenge is to combine the two attributes into a single QI. Here, by establishing spatial multimode, magnetic-field-insensitive and long-wavelength spin-wave storage in laser-cooled atoms inside a phase-passively-stabilized polarization interferometer, we constructed a multiplexed QI that stores up to three long-lived spin-wave qubits. Using a feed-forward-controlled system, we demonstrated that a multiplexed QI gives rise to a 3-fold increase in the atom–photon (photon–photon) entanglement-generation probability compared with single-mode QIs. For our multiplexed QI, the measured Bell parameter is 2.51±0.01 combined with a memory lifetime of up to 1 ms. This work represents a key step forward in realizing fiber-based long-distance quantum communications.

arXiv:2006.05631•Communications Physics•Jul 22, 2021•23 citations

Deterministic Generation of Light-Matter Entangled States for Realization of Quantum Repeaters

Priyanshu Tiwari, Aleksa Krstić, Frank Setzpfandt +2 more

Quantum repeaters are vital ingredients for realization of long-distance quantum networks [1]. They can be realized by preparing nodes that can generate an entangled light-matter state, namely, a single photon entangled to a quantum memory. This allows for entangling two distant quantum memories, by propagating the single photons from each node to an intermediate place for Bell state measurements. A common approach for generating such entangled light-matter states is generating an entangled photon pair in a nonlinear source, and coupling one of the photons in the pair to a quantum memory for storage [2]. However, such an approach faces two main challenges: Photon-pair generation in nonlinear sources is a probabilistic process. Moreover, due to modal and spectral mismatches, coupling single photons from a nonlinear source to a quantum memory is generally not an efficient process. These make the successful generation of an entangled light-matter state highly probabilistic.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 23, 2025•0 citations

Entanglement between a telecom photon and a room-temperature atomic-vapor quantum memory

Yang Wang, Alexander N. Craddock, Felipe Giraldo +3 more

We report experimental results of entangling a telecom photon and a long-lived atomic quantum memory, a key step in building a quantum repeater for long-distance quantum communications.

•Jan 1, 2024•0 citations
The light-matter quantum interface that can create quantum correlations or entanglement between a photon and one atomic collective excitation is a fundamental building block for a quantum repeater. The intrinsic limit is that the probability of preparing such nonclassical atom-photon correlations has to be kept low in order to suppress multiexcitation. To enhance this probability without introducing multiexcitation errors, a promising scheme is to apply multimode memories to the interface. Significant progress has been made in temporal, spectral, and spatial multiplexing memories, but the enhanced probability for generating the entangled atom-photon pair has not been experimentally realized. Here, by using six spin-wave-photon entanglement sources, a switching network, and feedforward control, we build a multiplexed light-matter interface and then demonstrate a ∼sixfold (∼fourfold) probability increase in generating entangled atom-photon (photon-photon) pairs. The measured compositive Bell parameter for the multiplexed interface is 2.49±0.03 combined with a memory lifetime of up to ∼51 μs.
A source that can generate atom-photon quantum correlations or entanglement based on a quantum memory is a basic building block of quantum repeaters (QRs). To achieve high entanglement generation rates in ensemble-based QRs, spatial-, temporal-, and spectral-multimode memories are needed. Previous temporal-multimode memories are based on rephasing mechanisms in inhomogeneously broadened media. Here, by applying a train of write pulses in time, with each pulse coming from a different direction, to a homogeneously broadened atomic ensemble to induce Duan-Lukin-Cirac-Zoller-like Raman processes, we prepare up to 19 pairs of modes, namely, one spin-wave mode and one photonic time bin. Spin-wave-photon (i.e., atom-photon) entanglement is probabilistically produced in these mode pairs. Based on the stored spin-wave modes together with feedforward-controlled readout, we build a temporally multiplexed source and then demonstrate an 18.8-fold increase in the probability of the generation of spin-wave-photon entanglement compared to the sources that use individual modes. The measured Bell parameter for the multiplexed source is $2.30\ifmmode\pm\else\textpm\fi{}0.02$, and the memory lifetime is 30 \ensuremath{\mu}s.
Practical realization of quantum repeaters requires quantum memories with high retrieval efficiency, multi-mode storage capacities, and long lifetimes. Here, we report a high-retrieval-efficiency and temporally multiplexed atom-photon entanglement source. A train of 12 write pulses in time is applied to a cold atomic ensemble along different directions, which generates temporally multiplexed pairs of Stokes photons and spin waves via Duan-Lukin-Cirac-Zoller processes. The two arms of a polarization interferometer are used to encode photonic qubits of 12 Stokes temporal modes. The multiplexed spin-wave qubits, each of which is entangled with one Stokes qubit, are stored in a "clock" coherence. A ring cavity that resonates simultaneously with the two arms of the interferometer is used to enhance retrieval from the spin-wave qubits, with the intrinsic retrieval efficiency reaching 70.4%. The multiplexed source gives rise to a ∼12.1-fold increase in atom-photon entanglement-generation probability compared to the single-mode source. The measured Bell parameter for the multiplexed atom-photon entanglement is 2.21(2), along with a memory lifetime of up to ∼125 µs.
Abstract Quantum interfaces (QIs) that generate entanglement between photonic and spin-wave (atomic memory) qubits are basic building block for quantum repeaters. Realizing ensemble-based repeaters in practice requires quantum memory providing long lifetimes and multimode capacity. Significant progress has been achieved on these separate goals. The remaining challenge is to combine the two attributes into a single QI. Here, by establishing spatial multimode, magnetic-field-insensitive and long-wavelength spin-wave storage in laser-cooled atoms inside a phase-passively-stabilized polarization interferometer, we constructed a multiplexed QI that stores up to three long-lived spin-wave qubits. Using a feed-forward-controlled system, we demonstrated that a multiplexed QI gives rise to a 3-fold increase in the atom–photon (photon–photon) entanglement-generation probability compared with single-mode QIs. For our multiplexed QI, the measured Bell parameter is 2.51±0.01 combined with a memory lifetime of up to 1 ms. This work represents a key step forward in realizing fiber-based long-distance quantum communications.
Quantum repeaters are vital ingredients for realization of long-distance quantum networks [1]. They can be realized by preparing nodes that can generate an entangled light-matter state, namely, a single photon entangled to a quantum memory. This allows for entangling two distant quantum memories, by propagating the single photons from each node to an intermediate place for Bell state measurements. A common approach for generating such entangled light-matter states is generating an entangled photon pair in a nonlinear source, and coupling one of the photons in the pair to a quantum memory for storage [2]. However, such an approach faces two main challenges: Photon-pair generation in nonlinear sources is a probabilistic process. Moreover, due to modal and spectral mismatches, coupling single photons from a nonlinear source to a quantum memory is generally not an efficient process. These make the successful generation of an entangled light-matter state highly probabilistic.