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Research Opportunities at LCLS September 2011. Joachim Stöhr. Five Revolutions in “light”. 1879 - Invention of the light bulb 1895 - Discovery of X-Rays 1960 - Invention of the LASER 1970 - Synchrotron radiation x-rays - SSRL 2009 - The first x-ray laser - LCLS.
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Research Opportunities at LCLS September 2011 Joachim Stöhr
Five Revolutions in “light” • 1879 - Invention of the light bulb • 1895 - Discovery of X-Rays • 1960 - Invention of the LASER • 1970 - Synchrotron radiation x-rays - SSRL • 2009 - The first x-ray laser - LCLS
The speed of things – the smaller the fast manifestation of the physical concept of “inertia” = resistance to motion, action, or change macro molecules molecular groups atoms “electrons” & “spins” Laser flash
The new science paradigm: Static “structure” plus dynamic “function” Present technological speeds Future technological speeds Lasers X-ray Lasers
Important areas of LCLS research Because of their size, atoms and “bonds” can change fast but how do systems evolve? key areas of interest: equilibrium (phase diagrams of complex materials…) close to equilibrium (operation or function of a system…) far from equilibrium (transient states like a chemical reaction…) far, far from equilibrium (matter during inertial confinement fusion…)
“Equilibrium”: What is the structure of water? Small angle x-ray scattering shows inhomogeneity Disordered soup Ice like clusters Components probably dynamic – form and dissolve - can we take an ultrafast snapshot??
“Close to equilibrium” – how does a device function: e.g. how does a spin current turn the magnetization ? magnetic switching today in 1 ns how fast can it be done? “bit” in cell Magnetic structure of “bit” Computer chip Electronic circuit Memory cell
“Far from equilibrium”:How does a chemical reaction proceed? reaction dynamics & intermediates end reaction products What are the key intermediate reactive species?
“Far, far from equilibrium”: Warm and hot dense matter The properties of matter in extreme states - which on earth can only be created transiently on ultrafast time scale- Sample
“Image before destroy” snapshotsfemtosecond protein crystallography • Atoms = electronic cores move slow enough so that • “image before destruction” becomes possible at LCLS • requirements: • maximum intensity for signal-to-noise • pulse length (~10 fs) shorter than atomic motion (100 fs)
LCLS facilities overview Injector electron beam 1km linac 14GeV AMO SXR Undulator hall XPP Near-hall: 3 stations XCS x-ray beam CXI Far-hall: 3 stations MEC
Experimental Halls and Operations Schedules Near Experimental Hall AMO SXRXPP X-ray Transport Tunnel 200 m XCS CXI MEC Start of operation AMO Oct-09 < 30Hz 60Hz 60Hz, 120Hz since Jan 2011 SXR May-10 XPP October-10 CXI February-11 Spring-12 XCS Far Experimental Hall MEC Fall-12
Optical laser versus X-ray free electron laser Optical laser X-ray laser • electrons in discrete energy states • stimulated emission amplified • through mirrors • fixed photon energy • low energy, long wavelength photons • compact • a bunch (~109) of free electrons • stimulated emission amplified • through electron ordering • tunable photon energy • high energy, short wavelength photons • large