LKB - Quantum Networks

Quantum Networks Team

The team focuses on experimental and theoretical researches to develop the scientific and technical abilities for the realization of quantum networks, with applications to the distribution and processing of quantum information. These works include the development of light-matter interfaces for quantum data storage, the generation, characterization and manipulation of various non-classical states of light, and the implementation of networking protocols using these resources.This research involves fundamental and more applied studies in quantum optics, light-matter interaction, non-linear optics, photon detection and nanophotonics. Three experiments are ongoing.

  • Adrien Cavaillès, Tom Darras, Giovanni Guccione, Julien Laurat
  • Jérémy Raskop, Jérémy Berroir, Alexandra Sheremet, Julien Laurat
  • Félix Hoffet, Mingtao Cao, Shuwei Qiu, Alexandra Sheremet, Julien Laurat
News and Events


Final review meeting for QSCALE: such a great project! More than 45 published papers!

SPIE talk

Julien is giving a talk at SPIE Optics+OptoElectronics about quantum memories: From free-space to all-fibered implementations.

Dr. Huang

Kun Huang successfully defended his thesis! ENS and ECNU Dr. Congratulations!


Julien and Aveek are attending the ONNA meeting in Okinawa. Thank you Sile for the invitation!


Julien is at IQIM-Caltech for 3 months! Back with Jeff!

NIST Boulder

Julien Laurat is visiting NIST Boulder. Superconducting!

Nature Com. Published

Congratulations to Valentina Parigi and Christophe Arnold! Our paper about vortex beam storage is published in Nature Communications!

PRL published!

Our PRL paper on the generation of large cat states is published in PRL. Congratulations to the Non-Gaussian team and our collaborators worldwide!

Kun Huang

Welcome back Dr. Huang! Now working with atoms!


Hanna is invited to the NTT-BRL School in Japan. She's also visiting Furusawa's Lab.

Best Poster at YQIS

Congratulations to Hadrien and Hanna! They won the Best Poster Award at YQIS'15!

Optics in 2015!

Our nanofiber memory highlighted in Optics in 2015 by Optics and Photonics News.

PQE 2016

Julien is at PQE 2016, Snowbird. Good snow and great meeting!

Dr. Gouraud !

Baptiste defended his PhD! Congratulations Dr. Gouraud!

Photonics West

Photonics West at San Francisco ! Invited talk in the Slow Light session. about our nanofiber work.


Our nanofiber memory featured in OPN this month: A Photonic Upgrade for Computer Memory.

Visit in Tokyo

Julien is visiting Furusawa's lab for one week.

CEWQO 2016

Julien is giving an invited talk at CEWQO 2016.

QCMC 2016

Two talks from our group at QCMC 2016. Hanna Le Jeannic about optical hybrid quantum information and Neil Corzo about our nanofiber-based experiments!


Our paper about Bragg reflection with the nanofiber-trapped atoms is accepted in PRL! Congratulations to all the nanofiber team!

ICAP 2016

Neil is attending ICAP 2016. He will present our nanofiber works: memory and Bragg mirror.

Superconducting detector

Our new paper with NIST and JPL on high-efficiency superconducting detectors is posted on arXiv !

Quantum Networks!

Julien is in Seefeld: Quantum networks brainstorming!

PRL online!

Our PRL on Bragg reflection with 2000 atoms is published. Featured nicely in a Focus by Physics!

Nature Com. Published!

Our Nature Communications on highly efficient quantum memory is published! See the Press Release and the Story!

PRL online!

Our PRL on slowing decoherence by squeezing in online. Congrats to the team and thank you Radim for the collaboration. Squeeeeeze!!

News and Views!

A News and Views written by Julien about two papers "Entanglement on demand" ! Congrats to Ronald's and Andreas' team !

Optica online !

Our Optica on remote state preparation is now published. Congrats to the Hybrid Photonics Team !

PRL online !

Our PRL on hybrid steering is now online ! A great collaboration!

QIA Launched!

Our Quantum Internet Alliance QIA flagship is officially launched!

Poster prize for Tom!

Congrats Tom! Poster prize at the Sirteq meeting!

QIA kick-off meeting

Mingtao and Felix at the kick-off meeting of QIA!

News: An all-fibered optical memory

static1.squarezespace.comThe team has recently managed to store light that propagates in an optical fiber and to release it later on demand. By causing interaction between the traveling light and a few thousand atoms in the vicinity, we demonstrated an all-fibered memory. At the core of the device is a fiber with a short section elongated to 400 nm in diameter where the light can efficiently interact with a cloud of laser-cooled atoms. Using the so-called electromagnetically induced transparency technique, well-known in free space but combined for the first time with a fiber, we slowed down the light by 3000-fold and then halted it completely. Later, the light was released into the fiber, reconstituting the initial encoded information that can once again travel. All that was performed at the single photon level with a signal to noise ratio above 20 !

This work was published in Physical Review Letters and selected as PRL Editors suggestions. Covered also by APS-Physics and PhysicsWorld. Selected by OSA Optics and Photonics News in Optics in 2015.

News: A mirror with only 2000 atoms

To manipulate light propagation, the simplest object one can thing of is a mirror. But usually a mirror is a macroscopic object composed of a very large number of atoms. The team has recently managed to demonstrate an efficient mirror constituted of only 2000 atoms!
By engineering the position of cold atoms trapped around a nanoscale fiber, we fulfilled the necessary conditions for Bragg reflection. Each atom contributes with a small reflectance, and the engineered position allows the constructive interference. The control of photon transport in waveguide coupled to atomic chains as realized here would allow for novel quantum network capabilities and many-body effects emerging from long-range interactions between multiple spins, a challenging prospect in free space.

Phys. Rev. Lett. 117, 133603 (2016)        The Focus by APS-Physics

Phd Student
  • Julien Laurat
  • Neil Corzo-Trejo
    Post Doctoral Researcher
  • Kun Huang
    Post Doctoral Researcher
  • Aveek Chandra
    PhD Student
  • Pierre Vernaz-Gris
    Phd Student
  • Adrien Cavailles
    Phd Student
  • Hanna Le Jeannic
    Phd Student
  • Baptiste Gouraud
    Phd Student
  • Yosuke Hashimoto
Recent Papers

Demonstration of Einstein-Podolsky-Rosen Steering Using Hybrid Continuous- and Discrete-Variable Entanglement of Light


A. Cavaillès et al.

Physical Review Letters 121, 170403 (2018)

Highly-efficient quantum memory for polarization qubits in a spatially-multiplexed cold atomic ensemble

P. Vernaz-Gris, K. Huang, M. Cao, A.S. Sheremet, J. Laurat

Nature Communications 9, 363 (2018)

Slowing Quantum Decoherence by Squeezing in Phase Space

H. Le Jeannic, A. Cavailles, K. Huang, R. Filip, J. Laurat

Phys. Rev. Lett. 120, 073603 (2018)

Large bragg reflection from one-dimensional arrays of trapped atoms near a nanoscale waveguide

N.V. Corzo, B. Gouraud, A. Chandra, A. Goban, A.S. Sheremet, D.V. Kupriyanov, J. Laurat

Phys. Rev. Lett. 117, 133603 (2016)


Interested in quantum optics and quantum information science? We are always happy to welcome motivated undergraduates, PhD students and Postdocs. See present offers for postdoc positions on Quantiki.

We are always looking for brillant motivated scientists to join our group.

We have presently open postdoc positions. See the offers on Quantiki here



Laboratoire Kastler Brossel, 4 place Jussieu, Case 74, 75252 Paris Cedex 05

LAURAT Julien – 01 44 27 30 64



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