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

Quantum Information and Measurement (QIM)

Hong-Ou-Mandel interference between two weak coherent pulses retrieved from room-temperature quantum memories

Alessia Scriminich, Mehdi Namazi, Mael Flament, Sonali Gera, Steven Sagona-Stophel, Giuseppe Vallone, Paolo Villoresi, Eden V. Figueroa

Published Jan 1, 2019• 1 citation
Publisher

Abstract

We measure Hong-Ou-Mandel interference between weak coherent pulses retrieved from room-temperature rubidium vapor quantum memories operating via Electromagnetically-Induced Transparency. The interference visibility of V = (46.8 ± 3.4)% makes the system suitable for Quantum Repeater applications.
DOI
10.1364/qim.2019.t5a.70

Related papers

Hong-Ou-Mandel interference of single-photon-level pulses stored in independent room-temperature quantum memories

Sonali Gera, Chase Wallace, Mael Flament +7 more

Abstract Quantum repeater networks require independent absorptive quantum memories capable of storing and retrieving indistinguishable photons to perform high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance for the realization of scalable quantum networks. We perform Hong-Ou-Mandel (HOM) interference between photonic polarization states and single-photon-level pulses stored and retrieved from two sets of independent room-temperature quantum memories. We show that the storage and retrieval of polarization states from quantum memories does not degrade the HOM visibility for few-photon-level polarization states in a dual-rail configuration. For single-photon-level pulses, we measure the HOM visibility with various levels of background in a single polarization, single-rail QM, and investigate its dependence on the signal-to-background ratio. We obtain an HOM visibility of 43%, compared to the 48% no-memory limit of our set-up. These results allow us to estimate a 33% visibility for polarization qubits under the same conditions. These demonstrations lay the groundwork for future applications using large-scale memory-assisted quantum networks.

npj Quantum Information•Jan 15, 2024•13 citations

Hong-Ou-Mandel interference of polarization qubits stored in independent room-temperature quantum memories

Sonali Gera, Chase Wallace, Mael Flament +7 more

Quantum repeater networks require independent quantum memories capable of storing and retrieving indistinguishable photons to perform high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance to the realization of scalable quantum networks. We perform Hong-Ou-Mandel (HOM) interference between photonic polarization qubits stored and retrieved from two sets of independent room-temperature quantum memories. We show a steady improvement in memory parameters and visibilities, culminating in a high quantum memory HOM visibility of 43%, compared to the 48% no-memory limit of our set-up. These results lay the groundwork for future applications using large-scale memory-assisted quantum networks.

arXiv:1808.07015•Aug 21, 2018•1 citation

Hong-Ou-Mandel interference of polarization qubits stored in independent room-temperature quantum memories

Mael Flament, Sonali Gera, Youngshin Kim +6 more

First generation quantum repeater networks require independent quantum memories capable of storing and retrieving indistinguishable photons to perform quantum-interference-mediated high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance in order to realize large scalable quantum networks. Here we address these significant challenges by observing Hong-Ou-Mandel (HOM) interference between indistinguishable photons carrying polarization qubits retrieved from two independent room-temperature quantum memories. Our elementary quantum network configuration includes: (i) two independent sources generating polarization-encoded qubits; (ii) two atomic-vapor dual-rail quantum memories; and (iii) a HOM interference node. We obtained interference visibilities after quantum memory retrieval of $\rm \boldsymbol{V=(41.9\pm2.0)\%}$ for few-photon level inputs and $\rm \boldsymbol{V=(25.9\pm2.5)\%}$ for single-photon level inputs. Our prototype network lays the groundwork for future large-scale memory-assisted quantum cryptography and distributed quantum networks.

•Aug 21, 2018•0 citations

A multi-node room-temperature quantum network

Mehdi Namazi, Mael Flament, Alessia Scriminich +5 more

First generation quantum repeater networks require independent quantum memories capable of storing and retrieving indistinguishable photons to perform quantum-interference-mediated high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance in order to realize large scalable quantum networks. Here we address these significant challenges by observing Hong-Ou-Mandel (HOM) interference between indistinguishable photons carrying polarization qubits retrieved from two independent room-temperature quantum memories. Our elementary quantum network configuration includes: (i) two independent sources generating polarization-encoded qubits; (ii) two atomic-vapor dual-rail quantum memories; and (iii) a HOM interference node. We obtained interference visibilities after quantum memory retrieval of $\rm \boldsymbol{V=(41.9\pm2.0)\%}$ for few-photon level inputs and $\rm \boldsymbol{V=(25.9\pm2.5)\%}$ for single-photon level inputs. Our prototype network lays the groundwork for future large-scale memory-assisted quantum cryptography and distributed quantum networks.

•Aug 21, 2018•0 citations

Hong–Ou–Mandel interference linking independent room-temperature quantum memories

Chao-Ni Zhang, Hang Li, Jian-Peng Dou +4 more

To realize a large-scale quantum network, both quantum memory and the interference of retrieved indistinguishable photons are essentially required to perform multi-photon synchronization and quantum-interference-mediated entanglement swapping. Significant progress has been achieved in low-temperature and well-isolated systems. However, linking independent quantum memories at room temperature remain challenging. Here, we present an experimental demonstration of Hong–Ou–Mandel interference between single photons from two independent room-temperature quantum memories. We manage to simultaneously operate two such quantum memories and individually obtain a memory-built-in quantum correlation of Stokes and anti-Stokes photons by a far-off-resonance Duan–Lukin–Cirac–Zoller protocol. We also successfully enhance the Hong–Ou–Mandel interference rate up to about 15 times by increasing each photon rate, which is achieved by coordinating two quantum memories with a repeat-until-success fashion. We observe the visibility of quantum interference up to 75.0% without reduction of any background noise, well exceeding the classical limit of 50%. Our results, together with its straightforward, broadband, and room-temperature features, open up a promising way towards realizing large-scale quantum networks at ambient conditions.

Photonics Research•Aug 16, 2022•7 citations

Toward Memory-Assisted Hong-Ou-Mandel Interference Between Two Independent Cavity-Enhanced Photon Pair Sources

Edoardo Buonocore, Sonali Gera, Eden V. Figueroa

We report our progress toward demonstrating memory-assisted Hong-Ou-Mandel interference between independent cavity-enhanced entangled photon pair sources at room temperature as a stepping stone toward a type II quantum repeater.

Quantum 2.0 Conference and Exhibition•Jan 1, 2025•0 citations
Abstract Quantum repeater networks require independent absorptive quantum memories capable of storing and retrieving indistinguishable photons to perform high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance for the realization of scalable quantum networks. We perform Hong-Ou-Mandel (HOM) interference between photonic polarization states and single-photon-level pulses stored and retrieved from two sets of independent room-temperature quantum memories. We show that the storage and retrieval of polarization states from quantum memories does not degrade the HOM visibility for few-photon-level polarization states in a dual-rail configuration. For single-photon-level pulses, we measure the HOM visibility with various levels of background in a single polarization, single-rail QM, and investigate its dependence on the signal-to-background ratio. We obtain an HOM visibility of 43%, compared to the 48% no-memory limit of our set-up. These results allow us to estimate a 33% visibility for polarization qubits under the same conditions. These demonstrations lay the groundwork for future applications using large-scale memory-assisted quantum networks.
Quantum repeater networks require independent quantum memories capable of storing and retrieving indistinguishable photons to perform high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance to the realization of scalable quantum networks. We perform Hong-Ou-Mandel (HOM) interference between photonic polarization qubits stored and retrieved from two sets of independent room-temperature quantum memories. We show a steady improvement in memory parameters and visibilities, culminating in a high quantum memory HOM visibility of 43%, compared to the 48% no-memory limit of our set-up. These results lay the groundwork for future applications using large-scale memory-assisted quantum networks.
First generation quantum repeater networks require independent quantum memories capable of storing and retrieving indistinguishable photons to perform quantum-interference-mediated high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance in order to realize large scalable quantum networks. Here we address these significant challenges by observing Hong-Ou-Mandel (HOM) interference between indistinguishable photons carrying polarization qubits retrieved from two independent room-temperature quantum memories. Our elementary quantum network configuration includes: (i) two independent sources generating polarization-encoded qubits; (ii) two atomic-vapor dual-rail quantum memories; and (iii) a HOM interference node. We obtained interference visibilities after quantum memory retrieval of V=(41.9±2.0)%\rm \boldsymbol{V=(41.9\pm2.0)\%}V=(41.9±2.0)% for few-photon level inputs and V=(25.9±2.5)%\rm \boldsymbol{V=(25.9\pm2.5)\%}V=(25.9±2.5)% for single-photon level inputs. Our prototype network lays the groundwork for future large-scale memory-assisted quantum cryptography and distributed quantum networks.
First generation quantum repeater networks require independent quantum memories capable of storing and retrieving indistinguishable photons to perform quantum-interference-mediated high-repetition entanglement swapping operations. The ability to perform these coherent operations at room temperature is of prime importance in order to realize large scalable quantum networks. Here we address these significant challenges by observing Hong-Ou-Mandel (HOM) interference between indistinguishable photons carrying polarization qubits retrieved from two independent room-temperature quantum memories. Our elementary quantum network configuration includes: (i) two independent sources generating polarization-encoded qubits; (ii) two atomic-vapor dual-rail quantum memories; and (iii) a HOM interference node. We obtained interference visibilities after quantum memory retrieval of V=(41.9±2.0)%\rm \boldsymbol{V=(41.9\pm2.0)\%}V=(41.9±2.0)% for few-photon level inputs and V=(25.9±2.5)%\rm \boldsymbol{V=(25.9\pm2.5)\%}V=(25.9±2.5)% for single-photon level inputs. Our prototype network lays the groundwork for future large-scale memory-assisted quantum cryptography and distributed quantum networks.
To realize a large-scale quantum network, both quantum memory and the interference of retrieved indistinguishable photons are essentially required to perform multi-photon synchronization and quantum-interference-mediated entanglement swapping. Significant progress has been achieved in low-temperature and well-isolated systems. However, linking independent quantum memories at room temperature remain challenging. Here, we present an experimental demonstration of Hong–Ou–Mandel interference between single photons from two independent room-temperature quantum memories. We manage to simultaneously operate two such quantum memories and individually obtain a memory-built-in quantum correlation of Stokes and anti-Stokes photons by a far-off-resonance Duan–Lukin–Cirac–Zoller protocol. We also successfully enhance the Hong–Ou–Mandel interference rate up to about 15 times by increasing each photon rate, which is achieved by coordinating two quantum memories with a repeat-until-success fashion. We observe the visibility of quantum interference up to 75.0% without reduction of any background noise, well exceeding the classical limit of 50%. Our results, together with its straightforward, broadband, and room-temperature features, open up a promising way towards realizing large-scale quantum networks at ambient conditions.