the Stanford Linear Accelerator Facility (SLAC) and Lawrence Berkeley
National Laboratory (LBNL) have selected Calmar Laser’s Cazadero
femtosecond fiber laser chirped pulse amplifier system for synchronized
time-resolved experiments that reveal unique structural changes in novel
Laser, a leading developer and manufacturer of ultrafast fiber lasers,
first introduced the Cazadero in 2005, primarily for precision materials
processing applications in medicine and microelectronics manufacturing.
However, the company says that within the research community there has
also been significant interest in the system, which provides up to 20 µJ
pulse energies at repetition rates up to a few MHz and a typical pulse
width of less than 500 fs.
selected the Cazadero because of its turn-key, stable performance and
compact size that enable convenient relocation of the system from one
experimental beam line to another. The combination of high repetition
rate and high energy, short pulses allows us to undertake picosecond
time–resolved x-ray studies with excellent signal-to-noise,” says
Professor Aaron Lindenberg at the SLAC facility.
Cazadero is operating at a repetition rate of 1.28 MHz and has been
successfully phase-locked to the synchrotron 476 MHz RF signal with a
timing jitter of less than 1 ps. The high energy output pulse of the
fiber based system is used to induce a change in a material system of
study, which is then interrogated at the atomic level by an x-ray pulse
from the synchrotron. The approach is used to gain a better
understanding of the excited state dynamics of nanocrystalline systems
and how they differ from the corresponding bulk materials. Such insight
could lead to more efficient next generation photovoltaic or biomedical
LBNL, Cazadero is enabling the development of a new light source known
as the Next Generation Light Source (NGLS). In this case, the laser is
again phase-locked but is used to irradiate a photocathode to produce
“bunches” of electrons that are accelerated to high energy in an RF
cavity. This system is being developed as the electron injector for the
NGLS. The NGLS is a Free Electron Laser producing X-rays into the keV
energy range and will be unique in operating at MHz repetition rate.
Depending on the choice of photocathode material, the laser will operate
at its fundamental 1030 nm wavelength, second harmonic, 515 nm, or
fourth harmonic, 257.5 nm.
choice of the photocathode laser system is critical in the design of a
machine devoted to support a user facility. We cannot tolerate any
human intervention on a daily basis. The Cazadero is a unique system
offering reproducible stable operation with a simple on/off switch. In
addition, it provides all the key technical specifications such as
power, repetition rate, and pulse duration for different types of
cathode as well as frequency locking,” says Howard Padmore, Experimental
Group systems leader.
NGLS, high repetition rate, high brightness X-ray source will enable
cinematic imaging of dynamics, determination of the structure of
heterogeneous systems, and development of novel nonlinear X-ray
SOURCE: Calmar Laser