The super-radiant laser project                         !! PhD and Post Doc positions open !! click here

Under controlled conditions, the collective emission of light by an ensemble of emitters leads to intriguing effects, such as the spontaneous emergence of entanglement and altered emission properties. We will make use of the collective spontaneous emission phenomenon called super-radiance, with thousands of atoms inside an optical cavity, to create a source of light with ultrastable frequency and a linewidth even below that of individual emitters. This novel source of coherent light is of particular interest for frequency metrology, as it may be used as optical clocks with improved robustness to perturbations, and possibly reduced experimental complexity.

A challenge for present-day super-radiant lasers is maintaining the emission continuously. The ambition of our project is to breach this milestone by continuously refilling the optical cavity with strontium atoms that were pre-excited on the intercombination transition. By using a simple thermal beam, we aim at establishing continuous operation in a relatively simple and robust design.

Continuous super-radiant laser. A thermal beam of strontium atoms, prepared in an excited electronic state, will be directed through an optical cavity. As super-radiance exacerbates their emission in the cavity mode, the system becomes a coherent light source with ultrastable frequency.


Igor Ferrier-Barbut, Laboratoire Charles Fabry de l'Institut d'Optique
Marion Delehaye, FEMTO-ST
Julian Robinson-Tait, University of Copenhaguen

Funding agencies

ANR, DIM Sirteq, Labex FIRST-TF

Project publications         (see abstracts in Recent results)

Correlations and linewidth of the atomic beam continuous superradiant laser, Bruno Laburthe-Tolra, Ziyad Amodjee, Benjamin Pasquiou, and Martin Robert-de-Saint-Vincent, SciPost Phys. Core 6, 015 (2023)


July 2023: Atoms have been seen in the main chamber, within the internship work of Arthur Ilman. The optical cavity of the superradiant laser (picture on the right) is ready to be installed in the vacuum.

February 2022: The superradiant laser optical cavity spacer has been made and polished by the laboratory optician Thierry Billeton.
                           Furthermore, the vacuum system is now assembled, but for the cavity.


January 2022: Welcome to Benjamin Pasquiou, new permanent member of the group!
                        And welcome to Ziyad Amodjee, post-doctoral researcher on the superradiant laser apparatus!

June 2021: Welcome to Grégoire Coget, research engineer, taking on the challenge of the design and construction of this machine!