GaP <110> crystal with a thickness of 200μm stuck
(optically contacted) on one GaP <100> with a thickness of 3mm
Aperture, mm 10 x 10 +/-0.1
Thickness of each component, mm 0.002 and 3 +/-10%
Orientation 110 -- 110
Surface quality, scr-dig 40-20 -- 40-20
Flatness, waves at 633 nm - 1
Parallelism, arc min < 3
Application - generation of T-rays (THz radiation, terahertz)
Feaatured customer: University of Bordeaux, France
COLA1 specifications in the CPMOH.
COLA1 in the CPMOH is operational since the second quarter of the year 2008.
This platform is built around an (2x4.5 mJ) amplified femtosecond Ti: Al2O3
laser that supplies two Infrared beams lines which deliver at 1 kHz repetition
rate, 50fs pulses, centered at 800 nm that have energy close to 4.5 mJ.
2.1. Tunable femtosecond beams.
The first beam line is exclusively dedicated to spectroscopic measurements. It
includes two Optical Parametric Amplifiers (“TOPAS-C”). Each of them is pumped
with 1 mJ. They generate tunable beams from 240 nm up to 22µm. The rest of the
energy can be used directly at 800 nm, it can be injected in frequency doubling
and tripling. These different supplied wavelengths can be used to excite
electronic and vibration modes of many molecules with a great temporal dynamic
ranging from few tens of femtoseconds up to hundreds of picoseconds.
2.2. T-Rays.
The second beam is dedicated to THz Time Resolved Spectroscopy and it deserves
several THz experiments.
Among these setups, one is a spectroscopic bench used to characterize materials
in the 100 GHz to 3.5 THz spectral range. This last one is synchronized
with two other Optical Parametric Amplifiers TOPAS which deliver tunable optical
beams in between 240 nm and 11µm. Thus this system makes possible to carry on
optical pump / THz probe experiments. Its originality is the use of tunable
femtosecond laser light that excite materials and measure their response in the
THz domain frequencies.
broadband THz bench. Frequency range 100 GHz – 3.5 THz
2.3. Detection tools.
We are able to characterize all kinds of samples (solid, liquid, crystal or
gas), and we use many detection systems adapted to the different wavelength
ranges. The beams lines are equipped with spectrometers, lock-in amplifiers,
data acquisition cards, photodiodes and pyroelectric detectors…
