Laser Systems
The ATF has two lasers, both with unique properties: A Nd:YAG laser and
a CO2 laser. The Nd:YAG laser(abbreviated
as YAG) serves as the illumination source for the ATF's photoinjector
and also operates an electro-optiv switch in the CO2 laser. The YAG light
can also be delivered to the experiment hall for use in experiments. This
laser has an exceptionally high stability and a great versatility in generating
variable length pulse trains with adjustable amplitude.
An actively mode-locked CW YAG oscillator generates a train of 1 nJ,
12 ns spaced pulses of linearly-polarized radiation synchronized with
the linac RF field. A Pockels cell switch, in combination with a polarizer,
cuts out single 15 ps FWHM pulses at a 3 Hz repetition rate. After a
4-pass preamplifier and a double-pass amplifier, pulses acquire 30 mJ
of energy. Part of this energy is directed through second and, then,
fourth harmonic crystals to a photocathode generating ~10 ps electron
bunches. The other portion is split to control the picosecond
slicing system . With the slicing system, we produce short, high
power pulses in the CO2 laser.
The CO2 laser is used for various experiments:
Laser acceleration of electrons, Harmonic Generation FEL (there the
CO2 laser is used as the subharmonic seed) or Compton backscattering
experiments. Currently this laser is being upgraded in power to
an unprecedented level. (See more under the CO2 laser
link).
The ATF and its
laser system is shown in the following schematic diagram
Last Modified: December 3, 2007
Please forward all questions about this site to:
Vitaly Yakimenko
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