Short presentation

Wave propagation in diffusive media is an important subject for numerous fields (medical imaging, acoustics, seismology, stellar physics, …). The experiments that we pursue make use of an original medium: a laser-cooled atomic cloud. The peculiar properties of this diffusive medium (strong resonances, strong nonlinearity, quantum internal structure of the scatterers, mechanical effects of light on the atoms, quantum effects…) give rise to a very rich physics. We study several subjects in this context. 
More generally, we are interested in collective effects in light-atom interaction, which include multiple scattering of light, but also nonlinear optics or cooperative scattering, in cold or hot vapors.
We have been also involved in a fruitful collaboration with astrophysicists on revival of intensity interferometry (Hanbury Brown and Twiss technique). 
Our work is mainly experimental, using four cold-atom apparatus and several smaller hot-vapor setups, but also theoretical, in particular through many collaborations.

Please look at our Research page to know more.

News & events

Sept. 2024: A workshop at Porquerolles

We're organizing a workshop on stellar intensity interferometry at Porquerolles in Septembre 2024. Check out the webpage of the event to know more!

April 2024: A new ERC grant for Robin Kaiser !


Robin's ERC proposal, called IC4Stars (Intensity Correlations for Stars) has been accepted! This is a follow-up of the ANR I2C project. This new grant will allow us to move forward much faster. Congratulations to Robin and to all the team involved!
See also the CNRS news release.

March 2024: Open PhD positions 

We have two open PhD positions to work on our cold-atom experiments. The first one will take place on Rb1, with Mathilde Hugbart: see this announcement. The second one will be on the new Ytterbium experiment, with Robin Kaiser and Raphaël Saint-Jalm: this announcement. Please contact us in you're interested.

Jan. 2024: Arrival

In January 2024, Daniel Benedicto Orenes has joined the ytterbium team with a Marie Curie Fellowship. Welcome Daniel!

Nov. 2023: Arrival and departure

On Mathilde's experiment "Rb1", one post-doc is leaving and another one has arrived. Hodei Eneriz will join the French quantum-computing Pasqal, and Juan Capella has joined our team after graduating from the Federal University of Pernambuco (Recife, Brazil). Good luck to both of you!

Oct. 2023: A special symposium for Robin Kaiser!


We have organized a two-day symposium to honor the 60th birthday of Robin Kaiser. Among many prestigious guests, Alain Aspect was here. Incredibly, we managed to keep the surprise for Robin until the last minute! The symposium has been a great success, with a good mixture of emotion and interesting scientific talks. Here is the webpage of the symposium for the full program and a few pictures.

On the left, Robin just discovering the plot with Alain Aspect :-)

Sept. 2023: Arrival and departures

  • At the end of July, Nolan Matthews left our team to go back to the US. Thanks a lot Nolan for your work, you have been the main driving force on the I2C project for more than two years. We wish you good luck for your career.
  • At the end of August, Romain Bachelard and Dilleys Ferreira left to go back to Brazil. That was very nice to have you guys.
  • On September 1st, Raphael Saint-Jalm , assistant professor at UCA, joined our team as a permanent member. Welcome Raphael!

July 2023: Open postdoc position

We open a postdoc position to work on the I2C project, please see the announcement.


May 2023: Robin and Nolan at Paranal (Chile)!

In the framework of the I2C project, Robin and Nolan had the chance to go to Chile for afive-night observing session on the Very Large Telescope facility at Mont Paranal in the Atacama desert. With our collaborator Jean-Pierre Rivet (OCA) we managed to adapt our setup for using three telescopes simultaneously and to observe the intensity correlations in the light of two different stars.

Feb. 2023: Congratulations Pierre and welcome Antoine!

Two events this month:
First, Pierre Lassègues successfully defended his thesis entitled "Étude des corrélations d'intensité dans la lumière diffusée par un gaz d'atomes froids". Congratulations and good luck for the following of your career, with a post-doc in Leuven (Belgium).
Second, we have been joined by Antoine Glicenstein as a post-doc, to work on the Ytterbium experiment. Antoine is already an expert in collective effects in light-atom interaction with a PhD thesis in the group of Antoine Browaeys at the Intsitut d'Optique. Good luck for your new project!


Nov. 2022: An Assistant-Professor position will open next year to join our team

In 2023 we'll hire an assistant professor (Maitre de Conference). The official announcement can be found here. Please contact Robin Kaiser if you're interested.


Oct. 2022: The physics Nobel Prize goes to Alain Aspect

Nobel prize
Nobel prize

It happens that most staff members of the team (Robin, Guillaume, Mathilde and William) are former PhD students of Alain Aspect! We are thus extremely happy that he has just won the Nobel Prize. Although the Nobel recognition is for earlier work to which none of us contributed, we're proud of our part of our career with him. He has been a great inspiration to all of us. Thank you and congratulations Alain!

Sept. 2022: Welcome to Dilleys and Romain

Two new postdocs have started this month. Dilleys Ferreira da Silva is joining the team working on the QuaCor project with Mathilde Hugbart, and Romain Caldani is joining the team working on the PACE-IN / 1DOrder projects with William Guerin. Welcome!


July 2022: New ANR project accepted !

The project 1DOrder aims at studying and using cold atomic samples having a 1D ordering for quantum-optical technolgies, especially quantum memories or quantum gates. It is a collaborative project between Etienne Brion, PI, doing theory at LCAR (Toulouse), Julien Laurat (co-PI) & Alban Urvoy, doing experiments with a chain of single atoms trapped near a nanofiber at LKB (Paris), and William Guerin (co-PI) of our group, doing experiments on cold atoms trapped in a 1D lattice.


July 2022: Visit of Lukáš Slodička

Lukáš Slodička, researcher in Olomouc University, visited our group for a few weeks in the framework of the PACE-IN project and UCA's wave complexity initiative. He's collaborating with Mathilde on the measurement of intensity-field correlations.

July 2022: Grant "Jeunes Docteurs Innovants" for Pierre Azam !

Pierre applied for a grant supported by the Région PACA for young innovative doctors. His project for a quantum simulator with hot atomic vapors has been selected. Congratulations!


March 2022: William and Mathilde at Paranal (Chile)!

The Dream Team
The Dream Team
In the framework of the I2C project, William and Mathilde had the chance to go to Chile for a six-night observing session on the Very Large Telescope facility at Mont Paranal in the Atacama desert. With our collaborator Jean-Pierre Rivet (OCA) we managed to adapt our setup to the 1.7 m telescopes and to observe the intensity correlations in the light of three different stars.

March 2022: Congratulations Ana!

On March 7th, Ana Cipris successfully defended her PhD thesis entitled "Long-lived collective modes of light in cold atoms: experimental and numerical studies on subradiance and Anderson localization". The committee manifested its great interest by asking high-level questions for 2h! Ana will soon start a post-doc in Zagreb. Good luck for the following of your career!


Fev. 2022: Welcome to Hodei Eneriz and welcome back to Romain Bachelard

After graduating from the University of Bordeaux, Hodei Eneriz is joining us as a post-doc. He's going to work on Rb1 with Martial, Pierre and Mathilde. Romain Bachelard is a long-time collaborator and he's going to be with us as invited researcher for one year. Welcome to both of you!

Jan. 2022: Two open postdoc positions

We have two open postdoc positions, for the Ytterbium and the Rubidium 2 experiments. See the announcement. EDIT: The positions have now been filled. But don't hesitate to contact us at any time for post-docs or PhD thesis, we may have something for you!

Nov. 2021: We're organizing the annual workshop of the "GDR Atomes froids"

This is an on-line event called "Cold-atom On-Line Meeting" (CoOLMe 2021) and it takes place from November 17th to 19th. See the dedicated website.

29 Sept. 2021: Pierre Azam successfully defended his PhD thesis!

Pierre's work on "Quantum fluids of light in hot atomic vapors" has been greatly appreciated by the committee. Pierre will remain in our group for some more time on an engineering project to make his experiment more compact, robust and automated, in view of future applications.

Sept. 2021: CoScaLi workshop at Porquerolles

Mathilde and Robin, with Romain Bachelard, have organized the 2021 workshop on Collective Scattering of Light (CoScaLi) on the beautiful island of Porquerolles. This hybrid event (both on-line and in-person) has been a success!

Sept. 2021: Our web page is back!

After several months of interruption and a lot of data loss (due to the fire of the data center), our cold-atom web page is finally back and can be updated again. But this is still a work in progress...