Femtosecond X-ray Pulses at 0.4 Å Generated by 90°
Thomson Scattering: A Tool for Probing the Structural Dynamics of
Materials
R. W. Schoenlein,
*
W. P. Leemans,
A. H. Chin,
P. Volfbeyn,
T. E. Glover,
P. Balling,
M. Zolotorev,
K.-J. Kim,
S. Chattopadhyay,
C. V. Shank
Pulses of x-rays 300 femtoseconds in duration at a wavelength of
0.4 angstroms (30,000 electron volts) have been generated by 90°
Thomson scattering between infrared terawatt laser pulses and highly
relativistic electrons from an accelerator. In the right-angle
scattering geometry, the duration of the x-ray burst is determined by
the transit time of the laser pulse across the 
90-micrometer waist
of the focused electron beam. The x-rays are highly directed (0.6°
divergence) and can be tuned in energy. This source of femtosecond
x-rays will make it possible to combine x-ray techniques with ultrafast
time resolution to investigate structural dynamics in condensed matter.
R. W. Schoenlein, T. E. Glover, P. Balling, Materials Sciences
Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
W. P. Leemans, P. Volfbeyn, M. Zolotorev, K.-J. Kim, S. Chattopadhyay,
Accelerator and Fusion Research Division, Center for Beam Physics,
Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
A. H. Chin, Department of Physics, University of California, Berkeley,
CA 94720, USA.
C. V. Shank, Materials Sciences Division, Lawrence Berkeley National
Laboratory, and Department of Physics, University of California,
Berkeley, CA 94720, USA.
*
To whom correspondence should be addressed.
