The team

Our team brings together rare and complementary profiles from the best entities in their field.

Their chemistry keeps Stellaria moving forward, regardless of age or background.

Nicolas Breyton

Founder and CEO

Nicolas Breyton graduated from the Institut National des Sciences Appliquées (INSA-Lyon) in Mechanical Engineering and has 25 years of international industrial experience. Initially employed by SNR Roulement for 7 years, Nicolas's passion for energy led him to join Schneider Electric for 17 years before founding Stellaria. He has held various positions in business development, major international project execution, product creation and decarbonisation strategy. Nicolas brings his vision of the industry to Stellaria's critical strategic orientations.

Guillaume Campioni

Founder and Technical Director

Co-founder and Technical Director Of Stellaria, Guillaume holds a PhD in nuclear physics and neutronics. Drawing on his network and 20 years' experience at the CEA, he relaunched work on molten-salt reactors in 2017 by coordinating the industry (CEA, Framatome, EDF, Orano, CNRS). Now an innovation trainer, he is co-founder and moderator of the MSR (Molten Salt Reactor) Bootcamp, an event whose “aim is to federate a community around the MSR object”. As Technical Director, he defines technical strategy brings together all the technical teams and is responsible for major scientific choices.

Bruno Desbrière

Founder and safety expert

After graduating in nuclear engineering, Bruno joined the CEA to work on reactors at the Grenoble Center (MELUSINE, SILOE, SILOETTE, etc.). Bruno then spent 15 years as Deputy Head of the Reactor Department at the Laue-Langevin Institute. In this role, he was responsible for safety and oversaw all the work to upgrade the High Flux Reactor following the Fukushima accident. Now retired, Bruno is a co-founder of Stellaria and brings his unrivalled expertise in reactor safety to the company.

Antoine Gerschenfeld

Founder and Assistant Technical Manager

A graduate of the Ecole Nationale Supérieure d'Ulm (ENS) with a thesis in theoretical physics, Antoine joined the CEA in 2013. He has worked in thermohydraulics on innovative reactor projects: ASTRID (sodium), NuWard (pressurised water) and ARAMIS (molten salts). Within the CEA, he has developed the computational codes needed to simulate neutronic and thermohydraulic phenomena in molten salt reactors. He has been involved in bilateral international collaborations with the USA, Japan, Russia and China, and multilateral collaborations with the IAEA, OECD and EURATOM. He is also a member of the FRAMATOME Scientific Advisory Board. It was his ideas and experience that led to the creation of Stellarium.

Lucas Tardieu

Founder and reactor architect

A graduate of the École nationale supérieure des arts et métiers (ENSAM) and of nuclear engineering, Lucas joined the CEA in 2020. He has worked on innovative nuclear reactor concepts, including sodium fast neutron, molten salt, and high-temperature and transportable reactors. He has also been a member of the CEA's Economic Intelligence Unit. He co-founded Stellaria in 2023 and now works as an applications engineer.

Amandine Calmet

PhD in Corrosion Chemistry

Baptiste Bernard

Thermal-hydraulic Engineer

Hamza Ghninou

PhD in Neutronics

Jean-Louis Durieu

Reactor Design Expert

Yoann Bomchil

Experimental Mechanical Engineer

Adrien Caillet

Industry Project Manager

Thomas Dumaire

PhD in Chemistry

Yannick Gorsse

Reactor Design Engineer

Aurélien Moureaux

Public Affairs and Funding Manager

Partners

CEA

The CEA is a major research player that serves the state, the economy, and the citizens. Based on excellence in fundamental research, it provides practical solutions to their needs in four main areas: low-carbon energies such as nuclear power and renewable energies, digital technologies, technologies for tomorrow's medicine, defence and security.

Orano

A specialist in nuclear energy, Orano's expertise covers the entire nuclear fuel cycle, from uranium mining to spent fuel recycling.

Schneider Electric

Schneider Electric aims to enable everyone to make the most of their energy and resources, reconciling progress and sustainable development. This ambition is called Life is On. Schneider Electric is the digital partner for sustainable development, energy efficiency, and the digital transformation of buildings and industry across the entire life cycle. Schneider Electric provides the most advanced energy and automation technologies, bringing connected electrical distribution and control platforms to the cloud.

Technip Energies

Technip Energies is a leading engineering and technology company serving the energy transition, with leading positions in liquefied natural gas (LNG), hydrogen and ethylene, and a strong presence in the growing markets for blue and green hydrogen, sustainable chemistry and carbon management. The company benefits from a robust project delivery model supported by various technologies, products and services. It operates in 35 countries and has 15,000 employees.

France 2030

France 2030 is a strategic investment plan launched by the French government to prepare France for the technological and industrial challenges of the next decade. With a budget of €54 billion, the plan covers several key sectors, including nuclear energy, where the government aims to regain its position as a world leader, while working towards a sustainable and innovative energy transition.

IJC Lab

The Irène Joliot-Curie Laboratory for the Physics of the 2 Infinites, or IJCLab, is a joint research unit of the CNRS, the Université Paris-Saclay and the Université de Paris, located on the Orsay campus and employing around 740 people. Its chemistry department brings together international experts in molten salts to study corrosion phenomena and synthesis methods. Since the beginning of 2024, the IJC laboratory has been home to the Stellaria chemistry team.

Join us

Our values are total honesty, science as our best judge, deep listening of the team from the management, no bullshit, risk-taking, entrepreneurship and rewarding mistakes, and intense customer satisfaction. We want to share the values of excellence, expertise, simplicity, passion and fun. Our head office is based in Grenoble, the beautiful city in the heart of the French Alps, just three hours from the Mediterranean.

Notre siège est à Grenoble, au pied des Alpes, où nous concevons notre réacteur tandis que notre laboratoire de chimie se trouve à Orsay, hébergé par l’IJCLab.

Are you looking for an inspiring job with a promising future? Then come and join us!