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  Centre Laser Infrarouge d'Orsay

cnrsUniversitÚ de Paris Sud   Laboratoire de Chimie Physique 
Introduction :  - Welcome
 - What is a Free-Electron Laser?
 - What for ?
Research topics :
 - A few recent topics
 - Publications
Set-up & performances :  - Accelerator
 - Laser
Experimental rooms:  - Diagnostics room
 - AFMIR-PTIR Microscopy
 - FTIR
 - Sum-frequency generation
 - FT-ICR spectrometry
 - Development
CLIO beamtime:  - Ask for CLIO beamtime
 - Refunding
Table top lasers:  - Forms
Links :
 -  Free-electrons lasers around the world
Infos & contacts :
 - Where ?
 - Who ?


What is a Free-Electron laser ?



FEL scheme'Conventional' lasers use excited atoms or molecules to amplify light.
Free-electron lasers (FEL) use a high-energy electron beam as an amplifying medium.

The electron beam emits light as it wiggles through a periodic magnetic structure called undulator. The light is stored in in an optical cavity, and can interact back with the electrons. This interaction leads to a modulation of the electronic density, and a growth in intensity and coherence of the emitted light.

The radiated wavelength depends on the energy of the electrons, the undulator period and the applied magnetic field. In principle, any wavelength can be  produced from X-ray to THz. But most FEL up to now operate in a wavelength range spanning from UV to far-infrared.

Limitations occur mostly from the electron beam quality and of course, the cumbersomeness and price of the required particle accelerators.
- A different laser
- Undulator radiation
- Coherence





ę 2012 LCP