The CLIO free electron laser ( Orsay, France)


Clio is located on the campus of Paris-Sud University in Orsay. Which puts it about 30 minutes from the center of Paris by public transport.


The Infrared Laser Center of Orsay (CLIO) is a light host, at the disposal of the scientific community since 1992. Until 2005, CLIO was one of the sources of LURE, the national synchrotron light center. At the closing of LURE, CLIO became a component of the LCP.

The host:

CLIO infrared laser facility is a linac based free-electron laser delivering tunable and powerful infrared radiation in short pulses. Its tuning range spans now from 3 to 150 µm. Complementary, Optical Parametric Oscillator (OPO) systems are also available at the CLIO facility, backing up the FEL for short wavelength operation (2-10 µm)  and kinetics involving pump-probe operation with different colors.

The time structure of CLIO is composed of 10 µs long train of pulses ("micropulse"), each "micropulse" being usually a few picoseconds long. In addition, the two-colours capability of CLIO is almost unique in the world, allowing two-colours pump-probe experiments tested up to 35 µm .

A purged beam line transports the optical beam to 7 user rooms. In addition to the FEL beam, ancillary equipment are proposed to users and several sophisticated permanent set-up are available for users :

  • FT-ICR-Mass spectrometers for molecules in gas phase spectroscopy by multiphoton dissociation
  • A near-field infrared microscope with spatial resolution < 100 nm capable of local spectroscopy
  • A pump-probe and photon echo experiment (no permanent scientist)

The proposals are reviewed by an international Programm Committee. The use of CLIO is free of charge for the academic community. Under the CALIPSOplus programm of the European Union, travel and living expenses may be refunded for researchers working in one of the States of the Community or Associated States, or in any foreign state, under certain limits.

Photon Beam Parameters Photon beam parameters
FEL mode Oscillator
Photon energy range / wavelength range 2500 - 150000 [nm]
Peak Photon energy / central wavelenght 10 * 103 [nm]
Photon energy/wavelength fluctuations 10 [%, RMS]
Fluctuations of the peak photon energy/central wavelenght 10%
Beam shape Gaussian
Pulse duration FWHM 5 [ps]
Polarisation Linear Horizontal
Pulse repetition rate 25 [Hz]
Maximum pulse energy 0.1 [mJ]
Peak power 100 * 106 [W]
Pointing stability at the source 100 [urad]
Pointing stability on target 1 [%]
Macropulse (train) duration 10 * 10-6 [sec]
Macropulse (train) repetition rate 25 [Hz]
Note Macro pulses of 10 µs at 25 Hz, containing 600 micro-pulses of 3 ps separated by 16 ns
Average power: 1W
Macro-pulse power: 4 kW
Micro-pulse power: 100 MW in 3 ps
Minimum spectral width : 0.2 % to 1 % (5 to 100 µm)
Relative wavelength stability: 0.1 %
Macro pulse length : 1 to 10 µs (tunable)
Micro pulse : 0.3 to 5 ps
Max. average power > 1 W ( 25 Hz, 16 ns/micro-pulses)
2-colors FEL tested up to 35 µm
Laboratoire de Chimie Physique
"Bâtiment 201 porte 2"20 rue Henri Becquerel"Universitée Paris-Sud"Orsay" Orsay
TEL. 33 1 69 15 32 99
CLIO Brillance
call for proposals

There is a call for projects per year for standard projects whose submission deadline is January 5th of the current year.