R&D Engineer in Optics and Numerical Simulations F/H

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Update on 23/10/2026

  • Contract type:  Permanent contract

  • Work time:  Full time

  • Location Rennes

The company

Founded in 2013, Cailabs designs, manufactures, and develops innovative photonic solutions for the space, industry, telecommunications, and defense sectors. A global specialist in laser shaping, the company has accelerated its growth in the space field with turnkey optical ground stations that integrate atmospheric turbulence compensation technology. This makes it one of the first companies to harness very high data rates enabled by optics in a commercial ground station.

Cailabs currently has more than 200 employees, including 41PhDs. With 29 patent families filed, the company is one of the most innovative companies in France. It is headquartered in Rennes, with offices in Paris and Washington (USA).

Post description

At Cailabs, we are looking for a PhD graduate in Physics to strengthen our Simulation team, bringing dual expertise at the intersection of optics and scientific computing.You will have the opportunity to lead innovative projects in free-space optical communications for space technologies, with the prospect of gradually taking responsibility for larger-scale technical topics.

Join Cailabs: Shape the future of optical technologies!

By joining our R&D department, you will take on exciting challenges and use your expertise to push the boundaries of what is possible in photonics. Within the Simulation team, you will apply your skills in optical simulation, experimental optics, optical system design, and Python programming for scientific computing.Following a PhD, potentially complemented by experience in industry or a postdoctoral position, you will join the technical experts within the Simulation team. You will work in a stimulating and collaborative environment offering strong intellectual challenges. You will contribute to a wide range of research and development projects in optics and will be responsible for the numerical simulation of various physical systems (laser beams, atmospheric turbulence, etc.).Within the Technical Department, you will join the Simulation team and report directly to the manager of this area of expertise.

Your main responsibilities will include:

  • Leading simulation studies to guide design decisions and strengthen the performance of existing free-space optical communication systems (e.g. the TILBA-OGS L10 optical ground station).
  • Conducting innovative and strategic studies for future generations of optical systems designed and manufactured by Cailabs, focusing on numerical simulation as well as fundamental and applied optics.

Profile required

  • You hold a PhD in Physics and have a background and experience in optics, gained during your PhD or later in your career, in either an experimental or theoretical environment.
  • You are creative and proactive, enjoy putting forward new ideas, and are motivated by turning them into practical applications.
  • You communicate confidently and collaborate effectively with a wide range of stakeholders.
  • You are able to discuss both technical topics and project organization in English.

Nice to have

  • Experience in experimental free-space optics, including setup, alignment and measurements.
  • Experience in an industrial environment, particularly working at the interface between product and production teams.
  • Skills in scientific computing with Python and an interest in programming in general.
  • Experience using optical modelling and simulation tools and numerical laser beam propagation codes, whether open-source or proprietary software such as Zemax.

Avantages

  • Opportunities to connect and enjoy time together as a team (annual seminar, team meals, games, sports activities, etc.).
  • 100% employer-funded health insurance.
  • A bonus scheme rewarding both collective and individual performance.
  • By joining Cailabs, you will become part of a dynamic team of engineers and PhD graduates who share your desire to apply their expertise to stimulating technical challenges. You will also have the opportunity to join a dynamic and agile company with the resources to match its ambitions, operating at the forefront of technology from prototype development through to industrialization.

Réf: a6d5e3f2-ab24-425d-9b32-fc05f1eb632c

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R&D Engineer in Optics and Numerical Simulations F/H

Permanent contract
Full time
Rennes

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