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

Emmagatzematge de single photons provinents d'un quantum dot in un vapor de Rb

Lara Scavuzzo

Published Jun 1, 2017• 0 citations
OpenAlex

Abstract

Quantum technologies open doors to outstanding applications, at the same time as they pose many scientific challenges. The promise of intrinsically secure communications relies on the implementation of quantum networks. However, noise in quantum channels sets a limit to both the range and the faithfulness of the communication link. To overcome these difficulties, quantum repeater schemes have been proposed to successfully transmit flying qubits (single photons) over long distances. The aim of this project is to advance towards the implementation of a fully functional quantum memory, a key element of any quantum repeater scheme. To do so, a hot rubidium vapor cell was employed, which takes advantage of electromagnetically induced transparency to perform the light storage process, using, in this case, light from a quantum dot. The novelty of the work resides on the fact that never has light from a quantum dot been stored in such a memory device. These objectives implied improving the transmission efficiency (from 5% to 14%) following numerous steps, as well as finding and characterizing a suitable quantum dot sample. The work in hand presents the numerous accomplishments that have been achieved, which set the realization of a quantum repeater very close to our reach.

Related papers

Storage of single photons in a hot Rubidium vapor

Lara Scavuzzo

Quantum technologies open doors to outstanding applications, at the same time as they pose many scientific challenges. The promise of intrinsically secure communications relies on the implementation of quantum networks. However, noise in quantum channels sets a limit to both the range and the faithfulness of the communication link. To overcome these difficulties, quantum repeater schemes have been proposed to successfully transmit flying qubits (single photons) over long distances. The aim of this project is to advance towards the implementation of a fully functional quantum memory, a key element of any quantum repeater scheme. To do so, a hot rubidium vapor cell was employed, which takes advantage of electromagnetically induced transparency to perform the light storage process, using, in this case, light from a quantum dot. The novelty of the work resides on the fact that never has light from a quantum dot been stored in such a memory device. These objectives implied improving the transmission efficiency (from 5% to 14%) following numerous steps, as well as finding and characterizing a suitable quantum dot sample. The work in hand presents the numerous accomplishments that have been achieved, which set the realization of a quantum repeater very close to our reach.

•Jun 1, 2017•0 citations

A cold atomic ensemble of rubidium for quantum storage ans single photon generation

Amandine Issautier, Anders Kastberg, Sébastien Tanzilli

Quantum communication aims at generating and distributing qubits between distant sites, in order to implement quantum information protocols, such as quantum key distribution, quantum teleportation and quantum processing. For many quantum protocols, and especially for quantum repeaters, which make quantum communication over long distances much more efficient, storage and/or emission of photonic states is necessary and represents a crucial step towards the realisation of a quantum network. An outstanding challenge of quantum communication is to implement quantum memories for photonic qubits, combining long storage time with high fidelity between the input and output states, and good efficiency. Moreover, to be compatible with quantum network applications, such as quantum repeaters, these memories have to enable heralded storage and on-demand read-out. Cold atomic ensembles hold promise for satisfying both these prerequisites, and are therefore a good candidate as storage medium, offering a compromise between different benchmarks. We are setting up an experiment intended to map polarisation qubits onto an optically pumped cold atomic ensemble of rubidium serving as our quantum memory device. In a first development, our quantum memory device will be operated in the single photon emission regime so as to implement, together with an entangled photon-pair source based on guided-wave optics, the quantum teleportation scheme.

•Jun 4, 2013•0 citations

Temperature Characterization of a Rubidium Vapor Electromagnetically Induced Transparency Quantum Memory

Konrad Artur Socha

Quantum communications aims to bring the quantum advantages to a large network. However, distributing quantum capabilities is a complicated task with many challenges. Electromagnetically induced transparency(EIT) based quantum storage is a candidate for implementation of quantum repeaters for the purpose of overcoming distance limitations in quantum communications. In this thesis we analyze the use of warm rubidium (Rb) vapor as a medium for a quantum memory. Starting by combining the Hamiltonian of a 2 level system with Maxwells equations we will model the interactions between light and the atomic system. We then examine simulations of the system and characterization of key features such as susceptibility and absorption. We are able to compare simulated spectroscopy models with spectroscopy data obtained from experiment to characterize the temperature of a rubidium vapor cell. These findings contribute to the ongoing development of quantum memory systems for efficient quantum repeaters.

•Jan 1, 2025•0 citations

Atomic vapor quantum memory for on-demand semiconductor single photon sources

Esteban Gómez-López, K. Winkler, Jonathan Jurkat +5 more

Quantum memories can substantially increase the efficiency of long-distance communications by synchronizing entanglement swapping operations in quantum repeater nodes. To build a quantum memory, electromagnetically induced transparency (EIT) in atomic vapors can be exploited to coherently store light pulses even at room temperatures. As a quantum source of light, semiconductor quantum dots (QD) offer bright on-demand single photons with high purity.4 Interfacing QDs with atomic vapors has been shown by “slow light” but a quantum memory for QDs is yet to be demonstrated. In this work, we develop an EIT quantum memory hosted in warm cesium vapor. Storage of faint coherent light pulses on the single photon level shows high storage efficiency. A measured bandwidth in the order of 200 MHz makes the memory compatible with the Fourier-limited emission of QDs embedded in micropillar cavities. We show the first attempts to interface the emission from a QD-micropillar with our quantum memory by finetuning the emission wavelength of the emitters to one of the hyperfine transitions in Cs, where the EIT memory takes place. This work sets the base for a hybrid quantum memory based on atomic ensembles for an on-demand semiconductor single-photon source.

Photonics for Quantum (PfQ)•Jul 19, 2023•1 citation

Quantum dot technology for quantum repeaters: from entangled photon generation towards the integration with quantum memories

Julia Neuwirth, Francesco Basso Basset, Michele B. Rota +5 more

The realization of a functional quantum repeater is one of the major research goals in long-distance quantum communication. Among the different approaches that are being followed, the one relying on quantum memories interfaced with deterministic quantum emitters is considered as among one of the most promising solutions. In this work, we focus on memory-based quantum-repeater schemes that rely on semiconductor quantum dots for the generation of polarization entangled photons. Going through the most relevant figures of merit related to efficiency of the photon source, we select significant developments in fabrication, processing and tuning techniques aimed at combining high degree of entanglement with on-demand pair generation, with a special focus on the progress achieved in the representative case of the GaAs system. We proceed to offer a perspective on integration with quantum memories, both highlighting preliminary works on natural-artificial atomic interfaces and commenting a wide choice of currently available and potentially viable memory solutions in terms of wavelength, bandwidth and noise-requirements. To complete the overview, we also present recent implementations of entanglement-based quantum communication protocols with quantum dots and highlight the next challenges ahead for the implementation of practical quantum networks.

arXiv:2104.07076•Apr 14, 2021•2 citations

An atomic memory suitable for semiconductor quantum dot single photons

Janik Wolters, Gianni Buser, Lucas Béguin +4 more

Summary form only given. Quantum networks consist of many quantum memory nodes that are interconnected via photonic links, transporting single photons carrying quantum information. In the future, such quantum networks may enable: high-speed quantum cryptography for unconditionally secure communication; large-scale quantum computers; and quantum simulators that will allow for exponential speed-up in solving specific complex problems. A promising route towards functional quantum network nodes is the heterogeneous approach [1], where different and separately optimized physical systems are used for single photon generation and storage. For example semiconductor quantum dots may be used as efficient, fast and deterministic single photon sources, while atomic ensembles allow for efficient storage of these photons.We demonstrate a photonic memory in warm Rb vapour with on-demand storage and retrieval, based on electromagnetic induced transparency (EIT). The memory is suitable for storing single photons emitted by a GaAs droplet quantum dots [2] embedded into a state-of-the-art photonic structures [3]. With our experiments we close the gap between low speed quantum memories with acceptance bandwidth well below 100 MHz and ultra-high speed memories with acceptance bandwidth above 1 GHz. We find that in this intermediate regime vapour cell memories offer an excellent compromise between storage efficiency, storage time and experimental complexity.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 1, 2017•1 citation
Quantum technologies open doors to outstanding applications, at the same time as they pose many scientific challenges. The promise of intrinsically secure communications relies on the implementation of quantum networks. However, noise in quantum channels sets a limit to both the range and the faithfulness of the communication link. To overcome these difficulties, quantum repeater schemes have been proposed to successfully transmit flying qubits (single photons) over long distances. The aim of this project is to advance towards the implementation of a fully functional quantum memory, a key element of any quantum repeater scheme. To do so, a hot rubidium vapor cell was employed, which takes advantage of electromagnetically induced transparency to perform the light storage process, using, in this case, light from a quantum dot. The novelty of the work resides on the fact that never has light from a quantum dot been stored in such a memory device. These objectives implied improving the transmission efficiency (from 5% to 14%) following numerous steps, as well as finding and characterizing a suitable quantum dot sample. The work in hand presents the numerous accomplishments that have been achieved, which set the realization of a quantum repeater very close to our reach.
Quantum technologies open doors to outstanding applications, at the same time as they pose many scientific challenges. The promise of intrinsically secure communications relies on the implementation of quantum networks. However, noise in quantum channels sets a limit to both the range and the faithfulness of the communication link. To overcome these difficulties, quantum repeater schemes have been proposed to successfully transmit flying qubits (single photons) over long distances. The aim of this project is to advance towards the implementation of a fully functional quantum memory, a key element of any quantum repeater scheme. To do so, a hot rubidium vapor cell was employed, which takes advantage of electromagnetically induced transparency to perform the light storage process, using, in this case, light from a quantum dot. The novelty of the work resides on the fact that never has light from a quantum dot been stored in such a memory device. These objectives implied improving the transmission efficiency (from 5% to 14%) following numerous steps, as well as finding and characterizing a suitable quantum dot sample. The work in hand presents the numerous accomplishments that have been achieved, which set the realization of a quantum repeater very close to our reach.
Quantum communication aims at generating and distributing qubits between distant sites, in order to implement quantum information protocols, such as quantum key distribution, quantum teleportation and quantum processing. For many quantum protocols, and especially for quantum repeaters, which make quantum communication over long distances much more efficient, storage and/or emission of photonic states is necessary and represents a crucial step towards the realisation of a quantum network. An outstanding challenge of quantum communication is to implement quantum memories for photonic qubits, combining long storage time with high fidelity between the input and output states, and good efficiency. Moreover, to be compatible with quantum network applications, such as quantum repeaters, these memories have to enable heralded storage and on-demand read-out. Cold atomic ensembles hold promise for satisfying both these prerequisites, and are therefore a good candidate as storage medium, offering a compromise between different benchmarks. We are setting up an experiment intended to map polarisation qubits onto an optically pumped cold atomic ensemble of rubidium serving as our quantum memory device. In a first development, our quantum memory device will be operated in the single photon emission regime so as to implement, together with an entangled photon-pair source based on guided-wave optics, the quantum teleportation scheme.
Quantum communications aims to bring the quantum advantages to a large network. However, distributing quantum capabilities is a complicated task with many challenges. Electromagnetically induced transparency(EIT) based quantum storage is a candidate for implementation of quantum repeaters for the purpose of overcoming distance limitations in quantum communications. In this thesis we analyze the use of warm rubidium (Rb) vapor as a medium for a quantum memory. Starting by combining the Hamiltonian of a 2 level system with Maxwells equations we will model the interactions between light and the atomic system. We then examine simulations of the system and characterization of key features such as susceptibility and absorption. We are able to compare simulated spectroscopy models with spectroscopy data obtained from experiment to characterize the temperature of a rubidium vapor cell. These findings contribute to the ongoing development of quantum memory systems for efficient quantum repeaters.
Quantum memories can substantially increase the efficiency of long-distance communications by synchronizing entanglement swapping operations in quantum repeater nodes. To build a quantum memory, electromagnetically induced transparency (EIT) in atomic vapors can be exploited to coherently store light pulses even at room temperatures. As a quantum source of light, semiconductor quantum dots (QD) offer bright on-demand single photons with high purity.4 Interfacing QDs with atomic vapors has been shown by “slow light” but a quantum memory for QDs is yet to be demonstrated. In this work, we develop an EIT quantum memory hosted in warm cesium vapor. Storage of faint coherent light pulses on the single photon level shows high storage efficiency. A measured bandwidth in the order of 200 MHz makes the memory compatible with the Fourier-limited emission of QDs embedded in micropillar cavities. We show the first attempts to interface the emission from a QD-micropillar with our quantum memory by finetuning the emission wavelength of the emitters to one of the hyperfine transitions in Cs, where the EIT memory takes place. This work sets the base for a hybrid quantum memory based on atomic ensembles for an on-demand semiconductor single-photon source.
The realization of a functional quantum repeater is one of the major research goals in long-distance quantum communication. Among the different approaches that are being followed, the one relying on quantum memories interfaced with deterministic quantum emitters is considered as among one of the most promising solutions. In this work, we focus on memory-based quantum-repeater schemes that rely on semiconductor quantum dots for the generation of polarization entangled photons. Going through the most relevant figures of merit related to efficiency of the photon source, we select significant developments in fabrication, processing and tuning techniques aimed at combining high degree of entanglement with on-demand pair generation, with a special focus on the progress achieved in the representative case of the GaAs system. We proceed to offer a perspective on integration with quantum memories, both highlighting preliminary works on natural-artificial atomic interfaces and commenting a wide choice of currently available and potentially viable memory solutions in terms of wavelength, bandwidth and noise-requirements. To complete the overview, we also present recent implementations of entanglement-based quantum communication protocols with quantum dots and highlight the next challenges ahead for the implementation of practical quantum networks.
Summary form only given. Quantum networks consist of many quantum memory nodes that are interconnected via photonic links, transporting single photons carrying quantum information. In the future, such quantum networks may enable: high-speed quantum cryptography for unconditionally secure communication; large-scale quantum computers; and quantum simulators that will allow for exponential speed-up in solving specific complex problems. A promising route towards functional quantum network nodes is the heterogeneous approach [1], where different and separately optimized physical systems are used for single photon generation and storage. For example semiconductor quantum dots may be used as efficient, fast and deterministic single photon sources, while atomic ensembles allow for efficient storage of these photons.We demonstrate a photonic memory in warm Rb vapour with on-demand storage and retrieval, based on electromagnetic induced transparency (EIT). The memory is suitable for storing single photons emitted by a GaAs droplet quantum dots [2] embedded into a state-of-the-art photonic structures [3]. With our experiments we close the gap between low speed quantum memories with acceptance bandwidth well below 100 MHz and ultra-high speed memories with acceptance bandwidth above 1 GHz. We find that in this intermediate regime vapour cell memories offer an excellent compromise between storage efficiency, storage time and experimental complexity.