Prof. Luc Thévenaz

Adjunct Professor

Luc Thévenaz received in 1982 the M.Sc. degree in astrophysics from the Observatory of Geneva, Switzerland, and in 1988 the Ph.D. degree in physics from the University of Geneva, Switzerland. He developed at this moment his field of expertise, i.e. fibre optics.
In 1988 he joined the Swiss Federal Institute of Technology of Lausanne (EPFL) where he currently leads a research group involved in photonics, namely fibre optics and optical processsing and sensing.

His main achievements are:
- the invention of a novel configuration for distributed Brillouin fibre sensing based on a single laser source, resulting in a high intrinsic stability making for the first time field measurements possible,
- the development of a photoacoustic gas trace sensor using a near infra-red semiconductor laser, detecting a gas concentration at the ppb level,
- the first experimental demonstration of optically-controlled slow & fast light in optical fibres, realized at ambient temperature and operating at any wavelength since based on stimulated Brillouin scattering. The first negative group velocity of light was also realized in optical fibres using this approach.

He joined in 1998 the company Orbisphere Laboratories SA in Neuchâtel, Switzerland, as Expert Scientist to develop gas trace sensors based on photoacoustic laser spectroscopy.
In 2000 he co-founded the spin-off company Omnisens that is developing and commercializing advanced photonic instrumentation.

During his career he made academic stays in several Universities, such as the Korea Advanced Institute of Science and Technology (KAIST), Shanghai JiaoTong University and Tel Aviv University.

He is author or co-author of some 250 publications and 5 patents.


Research Area

The Group occupies a leading position on the global research scene in distributed fibre sensing based on optical nonlinearities. This type of sensors is foreseen to be an essential tool to secure critical installations, such as dams, tunnels and pipelines.

The team could demonstrate for the first time the possibility to modify and to control the speed of a light signal in an optical fibre, offering an important timing tool that was missing in the photonics domain. This has impacted on all applications in which a proper time sequence is important, such as telecommunication networks, optical computing and the processing of complex light signals. These novel functions are achieved by using nonlinear optical interactions and novel types of fibres showing a photonic crystal structures.

A technique leading to a dramatic increase in the capacity of optical fibres has also been recently achieved that reduces the amount of space required between the pulses of light that transport data, using the so-called Nyquist pulses to an unmatched perfection. The breakthrough could increase the throughput of data in telecommunications systems by a factor of ten.


ELE 138 (Bâtiment ELE)
Station 11
CH-1015 Lausanne