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

Physica Scripta

Heralded atomic-ensemble quantum memory for photon polarization states

Haruka Tanji, Jonathan Simon, Saikat Ghosh, Benjamin Bloom, Vladan Vuletić

Published Jul 1, 2009• 3 citations
Publisher

Abstract

We describe the mapping of quantum states between single photons and an atomic ensemble. In particular, we demonstrate a heralded quantum memory based on the mapping of a photon polarization state onto a single collective-spin excitation (magnon) shared between two atomic ensembles. The polarization fidelity above 90(2)% for any input polarization far exceeds the classical limit of \frac{2}{3} . The process also constitutes a quantum non-destructive probe that detects and regenerates a photon without measuring its polarization.

DOI
10.1088/0031-8949/2009/t135/014010

Related papers

Heralded single-magnon quantum memory for photon polarization states

Haruka Tanji, Saikat Ghosh, Jonathan Simon +2 more

We demonstrate a heralded quantum memory based on mapping of a photon polarization state onto a single collective-spin excitation (magnon) shared between two spatially overlapped atomic ensembles. The polarization fidelity is measured by quantum state tomography to be above 90(2)% for any input polarization, which far exceeds the classical limit of 2/3. The process also constitutes a quantum non-destructive probe that detects and regenerates a photon without touching its - potentially undetermined - polarization.

arXiv:0808.3603•Aug 27, 2008•3 citations

Heralded Single-Magnon Quantum Memory for Photon Polarization States

Haruka Tanji, Saikat Ghosh, Jonathan Simon +2 more

We demonstrate a heralded quantum memory where a photon announces the mapping of a light polarization state onto a single collective-spin excitation (magnon) shared between two atomic ensembles. The magnon can be converted at a later time into a single polarized photon with polarization fidelity over 90(2)% for all fiducial input states, well above the classical limit of 2/3. The process can be viewed as a nondestructive quantum probe where a photon is detected, stored, and regenerated without touching its-potentially undetermined-polarization.

Physical Review Letters•Jul 20, 2009•86 citations

Heralded amplification for precision measurements with spin ensembles

Nicolas Brunner, Eugene Simon Polzik, Christoph Simon

We propose a simple heralded amplification scheme for small rotations of the collective spin of an ensemble of particles. Our protocol makes use of two basic primitives for quantum memories, namely, partial mapping of light onto an ensemble, and conversion of a collective spin excitation into light. The proposed scheme should be realizable with current technology, with potential applications to atomic clocks and magnetometry.

arXiv:1107.2828•Physical Review A•Oct 17, 2011•7 citations

Entanglement and quantum memory with atomic ensembles

Eugene Simon Polzik, Brian Julsgaard, Jens Lykke Sørensen +1 more

Summary form only given. A new approach to the problem of the quantum interface between light and atoms has been recently developed. The method utilizes free space dispersive interaction between pulses of light and spin polarized atomic ensembles. Entanglement between the polarization state of light and the collective spin state of atoms is established by measurement, more precisely by detection of light in a certain polarization basis. In the first demonstration of this approach we have generated a long-lived entangled state of two separate macroscopic atomic samples by a polarization measurement on light transmitted through the samples. We then have shown that this approach also works for mapping of a quantum state of light onto long-lived atomic spin state paving the road towards realization of the quantum memory for light. Recently we have also extended the free space light-atoms interface beyond the continuous variables in the proposal, where a coherent superposition "cat" state of an atomic ensemble is generated by a measurement sequence. Progress with other communication protocols such as atomic state teleportation and multiparty networks will be presented.

European Quantum Electronics Conference (EQEC)•Jan 1, 2003•0 citations

An optically pumped cold atomic ensemble for heralded storage of polarization qubits

Amandine Issautier, Sébastien Tanzilli, Anders Kastberg

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 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.

•Nov 23, 2011•0 citations

Heralded Storage of a Photonic Quantum Bit in a Single Atom

Norbert Kalb, Andreas Reiserer, Stephan Ritter +1 more

Combining techniques of cavity quantum electrodynamics, quantum measurement, and quantum feedback, we have realized the heralded transfer of a polarization qubit from a photon onto a single atom with 39% efficiency and 86% fidelity. The reverse process, namely, qubit transfer from the atom onto a given photon, is demonstrated with 88% fidelity and an estimated efficiency of up to 69%. In contrast to previous work based on two-photon interference, our scheme is robust against photon arrival-time jitter and achieves much higher efficiencies. Thus, it constitutes a key step toward the implementation of a long-distance quantum network.

arXiv:1503.06709•Physical Review Letters•Jun 2, 2015•107 citations
We describe the mapping of quantum states between single photons and an atomic ensemble. In particular, we demonstrate a heralded quantum memory based on the mapping of a photon polarization state onto a single collective-spin excitation (magnon) shared between two atomic ensembles. The polarization fidelity above 90(2)% for any input polarization far exceeds the classical limit of \frac{2}{3} . The process also constitutes a quantum non-destructive probe that detects and regenerates a photon without measuring its polarization.
We demonstrate a heralded quantum memory based on mapping of a photon polarization state onto a single collective-spin excitation (magnon) shared between two spatially overlapped atomic ensembles. The polarization fidelity is measured by quantum state tomography to be above 90(2)% for any input polarization, which far exceeds the classical limit of 2/3. The process also constitutes a quantum non-destructive probe that detects and regenerates a photon without touching its - potentially undetermined - polarization.
We demonstrate a heralded quantum memory where a photon announces the mapping of a light polarization state onto a single collective-spin excitation (magnon) shared between two atomic ensembles. The magnon can be converted at a later time into a single polarized photon with polarization fidelity over 90(2)% for all fiducial input states, well above the classical limit of 2/3. The process can be viewed as a nondestructive quantum probe where a photon is detected, stored, and regenerated without touching its-potentially undetermined-polarization.
Summary form only given. A new approach to the problem of the quantum interface between light and atoms has been recently developed. The method utilizes free space dispersive interaction between pulses of light and spin polarized atomic ensembles. Entanglement between the polarization state of light and the collective spin state of atoms is established by measurement, more precisely by detection of light in a certain polarization basis. In the first demonstration of this approach we have generated a long-lived entangled state of two separate macroscopic atomic samples by a polarization measurement on light transmitted through the samples. We then have shown that this approach also works for mapping of a quantum state of light onto long-lived atomic spin state paving the road towards realization of the quantum memory for light. Recently we have also extended the free space light-atoms interface beyond the continuous variables in the proposal, where a coherent superposition "cat" state of an atomic ensemble is generated by a measurement sequence. Progress with other communication protocols such as atomic state teleportation and multiparty networks will be presented.
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 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.
Combining techniques of cavity quantum electrodynamics, quantum measurement, and quantum feedback, we have realized the heralded transfer of a polarization qubit from a photon onto a single atom with 39% efficiency and 86% fidelity. The reverse process, namely, qubit transfer from the atom onto a given photon, is demonstrated with 88% fidelity and an estimated efficiency of up to 69%. In contrast to previous work based on two-photon interference, our scheme is robust against photon arrival-time jitter and achieves much higher efficiencies. Thus, it constitutes a key step toward the implementation of a long-distance quantum network.