science / reaction dynamics
/ laser photochemistry /
interactions / nanotechnology
chemistry / chemical physics
Photochemistry in the VUV
This project was part of a TMR Network which you can learn
more about here.
Being part of a TMR network is often hard work, including walking
up snowy mountain roads and skiing. During this work, we built a rather
unique machine to study ultrafast
(about 1 ps or less) photochemistry in the vacuum ultraviolet regime.
A schematic drawing of the apparatus appears below. The required
photons were made through a
laser-based technique: high
harmonic generation with an Ar-ion-pumped
Ti:sapphire laser . This laser produces roughly 80 fs pulses at a
wavelength near 800
nm. The output of the Ti:sapphire laser is focused into a rare gas that
flows out of a tube in a vacuum chamber, as shown in the photo on the
nonlinear interaction between the laser field and the atoms in the rare
gas jet creates the photons that we are after: ~10-40 eV or 120-30 nm.
We studied the photochemistry
of O 2 adsorbed on graphite.
This was the first use of HHG to initiate surface photochemistry.
To learn more about lasers, try this tutorial.
For further information on related topics, try these sites:
Attosecond physics in Lund
Attosecond and High Field Physics at the MPI Garching (These guys do incredible work but
this is the worst website ever. To be fair, I'm sure it's a work in progress.)
High Harmonic Generation
Movies of HHG
More on HHG
Labs working in Surface Science, Nanotechnology and Catalysis
Dynamics of Gas-Surface Interactions