Lawrence Berkeley National Laboratory
A partnership of several Divisions at LBNL, coordinated through the Advanced Photon Science Initiative, is working to address the needs of the primary scientific Grand Challenges now being considered by the Department of Energy, Basic Energy Sciences. We are exploring scientific discovery opportunities, and new areas of science, to be unlocked with the use of advanced photon sources. To meet these needs, we propose a seeded, high repetition-rate, free-electron laser (FEL) facility. Temporally and spatially coherent photon pulses, of controlled duration from picosecond to the attosecond regime, are within reach in the VUV to soft X-ray regime. LBNL is developing accelerator physics and technologies in an R&D program that will ultimately lead to a facility with an array of high repetition rate FELs, each independently configurable and tunable, providing a range of photon beams with high average and peak flux and brightness.
The Advanced Photon Science Initiative addresses the scientific needs of the future, such as understanding the dynamics and “emergent” properties of complex systems arising from correlated interactions between charge carriers and constituent atoms. Direct quantitative measurements of the electronic and atomic structural dynamics on the ultrafast time scale of the underlying correlations will be indispensable in achieving new insight into the complex properties emerging from correlated phenomena in atoms, molecules, and solids. The fundamental time scales span:
• ~Picoseconds, characteristic
of conformational relaxations in molecular systems and electron-lattice
energy transfer times in crystalline solids.
• ~100 femtoseconds,
characteristic of atomic vibrational periods in molecules and solids
• ~10
femtoseconds, characteristic of electron-electron scattering times in
solids
• ~100 attoseconds, characteristic of electron-electron
correlations and valence electron motion.
