Trends in X-ray Synchrotron Radiation Research Storage rings Energy Recovery Linacs (ERL) Free Electron Lasers Jochen R. Schneider DESY
Development of the brilliance of X-ray sources Since the discovery of X-rays in 1895 the average brilliance increased by more than 3 orders of magnitude every 10 years. However, today s storage ring technology approaches its theoretical limits 2
Compact Light Source (CLS) 2 March 2006: Today, Ronald Ruth, Ph.D., president of Lyncean Technologies, announced that the CLS prototype is up and running and has just produced its first X-ray beams "With the production of its first X-ray beam, the CLS has now demonstrated its feasibility," said Jeremy M. Berg, Ph.D., director of NIGMS. "The option for having such intense, tunable X-ray sources on site at many institutions has the potential to transform numerous fields of biomedical research." 3
Synchrotron radiation + Opening of new opportunities at existing 3 rd generation sources Undulators Optics, especially focusing: KB mirrors, zone plates, refractive lenses Sample environment: Extreme conditions Detectors General user software Establishing strong in-house research programmes Connections to Universities Science centers on site: Nano Science Centers in the US, Carl Branden Center at ESRF Trend to long beamlines (pioneered at SPring-8) 4
Long beamlines at 3 rd generation facilities Free Electron Laser Shanghai Synchrotron Radiation Facility 5
Long beamlines at 3 rd generation facilities Free Electron Laser Shanghai Synchrotron Radiation Facility 6
NSLS-II: Ultra-high Brightness Medium Energy Third Generation Storage Ring and IR Ring Highly Optimized X-ray Storage Ring Dedicated Enhanced Infrared Ring 800 MeV, 1000 ma, Top-off Injection BROOKHAVEN SCIENCE ASSOCIATES 3 GeV, 500 ma, Top-off Injection 24 Cell, Triple Bend Achromat Circumference 620 m 21 Insertion Device Straight Sections (7 m) 24 Bending Magnet Ports Ultra-Low Emittance (ε x, ε y ) (Diffraction limited in vertical at 10 kev) Brightness ~ 10 21 p/s/0.1%bw/mm 2 /mrad 2 Flux ~ 10 16 p/s/0.1%bw Beam Size (σ x, σ y ) Beam Divergence (σ x, σ y ) Pulse Length (rms) 1.5, 0.008 nm 84.6, 4.3 μm 18.2, 1.8 μrad 11 psec Exceptional intensity and position stability Upgradeable to ERL operation in future improvement of emittance by installing damping wigglers 7
Coherence: Nano-scale holography (~50 nm) Magnetism hologram S. Eisebitt et al. (2004) BESSY & SSRL 8
Spectral distribution of average brilliance PETRA III: 6 GeV, 2.3 km circumference, damping wigglers extension to higher photon energies cold in-vacuum undulators, undulators in super-conducting technology 9
High energy synchrotron radiation High penetration power, Momentum space geometry like 100 kev Electrons E ~ 100 kev k f k i Ewald sphere (010) (001) scattering pattern 1 Million data points parallel (100) sample 2D-detector 10
Diffuse X-ray scattering studies on alloys Cu 3 Pd A. Schöps, Ph.D. Thesis, 2003 Au 3 Ni H. Reichert et al., 2003 Detailed information on the interatomic potentials Complex phase behavior due to interplay of ordering and phase separation in the same system 60-80 kev Synchrotron Radiation 11
Short pulse option with deflecting cavities courtesy M. Borland 12
Short pulse option with deflecting cavities 13
Development of the brilliance of X-ray sources X-ray Laser Since the discovery of X-rays in 1895 the average brilliance increased by more than 3 orders of magnitude every 10 years. However, today s storage ring technology approaches its theoretical limits: A new X-ray source is needed for studies of the dynamic state of matter on nature s time scales Linac driven Free-Electron Lasers open the new horizon. 14
Peak brilliance of pulsed X-ray sources Peak Brightness [Phot./(s mrad 2 mm 2 0.1%bandw.)] X-Ray FELs Initial ERLs 3 rd Gen. SR 2 nd Gen. SR Initial Laser Slicing SPPS Future Future Ultrafast x-ray sources will probe space and time with atomic resolution. H.-D. Nuhn, H. Winick FWHM X-Ray Pulse Duration [ps] 15
Slicing at medium energy storage rings Schoenlein, Chattopadhay, Chong, Glover, Heimann, Shank, Zholents, Zolotorev Science 287 (2000) 2237 16
Light triggered transition from low-spin to high-spin state static difference to ground state optical measurements Christian Bressler et al. (EPFL Lausanne) 17
Sub-Picosecond Pulse Source (SPPS) 20 psec Damping Ring (ge 30 mm) m) SLAC Linac FFTB line 1 GeV 4 psec 0.2 psec 28 GeV <100 fsec Add Add 12-meter 12-meter chicane chicane compressor compressor in in linac linac at at 1/3-point 1/3-point (9 (9 GeV) GeV) diffuse scattering from SALOL Existing ends compress to <100 fsec 1.5 Å ~10 6 photons/pulse @ 9.365 kev 1 x 1 mm 2, 1% bandwidth, 300 s, 10 Hz I /ka σ z = 28.0 μm (FWHM: 24.6 μm, Gauss: 11.0 μm) 30 I = 30.631 ka pk 25 20 15 10 5 0 0.1 0.2 0.3 z /mm 80 fsec FWHM 18
Results from SPPS in Stanford This measurement indirectly determined the arrival time of each x-ray pulse relative to an external pump laser pulse with a time resolution of better than 60 fs rms. 19
Schematic layout of a single pass XFEL 20
FLASH: the VUV-FEL User Facility at DESY RF gun Laser M1 M2 M3 M4 M5 M6 M7 bunch compressor bunch compressor collimator 4 MeV 150 MeV 450 MeV 1000 MeV undulator s bypass FEL experimental area 250 m 21
FLASH: Lasing at 13.1 nm, ~5 µj (26.4.2006) Single shot spectrum Single shot beam profile on Ce:YAG crystal Spectrum (average of 1000 shots) Energy (µj) Bunch Number intensity fluctuations max average single 22
FLASH: Lasing at 13.1 nm, ~5 µj (26.4.2006) 23
FLASH: Lasing at 25.5 nm (May 2006) Double slit diffraction 30 µj 0.15 mm slit distance Single shot spectrum 3rd harmonic at 8.5 nm (2500 shots) 0.6 mm slit distance 24
Improved beam properties by self-seeding Spectrum before - after seeding 25
High-Gain Harmonic-Generation (HGHG) Li Hua Yu (Brookhaven National Lab) HGHG laser e - modulator dispersive section radiator Intensity, a.u. Wavelength, nm SASE 10 4 Cascading HGHG Stages to Generate Coherent Soft X-ray P in =500MW 400MW 800MW 70MW P out =1.7GW 266nm 53.2nm 10.64nm 2.12nm 2.12nmm e-beam 750Amp 1mm-mrad 2.6GeV σ γ / =2 10-4 26
Properties of XFEL radiation Compared to 3 rd generation storage ring based synchrotron radiation facilities, the gain factors are: peak brilliance: average brilliance: coherence: 10 9 at the FEL line 10 4 spontaneous 10 4 at FEL line 10 9 at FEL line x10 9 Scientific goal: Probing the dynamic state of matter with atomic resolution in space and time Peak brilliance 27
Hard X-ray SASE Free Electron Lasers LINAC COHERENT LIGHT SOURCE LCLS 2009 2010 SCSS SPring-8 Compact SASE Source European XFEL Facility 2012 FLASH in operation 28
Challenges for Science at FEL Facilities Experiments at XFEL injector LINAC FEL process sample spectrometer detector data handling VUV-FEL DESY LCLS Stanford FEL process: pulse shaping e- and photon beam diagnostics, synchronization mechanical stability (10 fs 3 µm) interaction of FEL beam with matter sample preparation sample environment (pump lasers, synchronization) detector development data processing data analysis 29
Imaging of a single bio-molecule with atomic resolution Lysozym single molecule crystal Oversampling: J. Miao, K.O. Hodgson and D. Sayre, PNAS 98 (2001) 6641-6645 30
Coulomb Explosion von Lyzosym t=0 Coulomb explosion of Lysozyme Coulomb explosion of lysozyme (50 fs) 50 fs 3x10 12 photons/100 nm spot 12 kev LCLS t=50 fsec t=100 fsec Radiation damage interferes with atomic scattering factors and atomic positions 28 Firmenam e (Referentennam e) R. Neutze, R. Wouts, D. van der Spoerl, E. Weckert, J. Hajdu: Nature 406 (2000) 752-757 31
Ultrafast coherent diffraction with 32 nm X-rays FLASH Incident FEL pulse: 30 fs, 32 nm, 3x10 13 W cm -2 H. Chapman, J. Hajdu et al. 32
Ultrafast coherent diffraction FLASH diffraction pattern from first pulse diffraction pattern from second pulse reconstructed picture TEM picture from original structure H. Chapman, J. Hajdu et al. 33
Ultrafast coherent diffraction FLASH H. Chapman, J. Hajdu et al. diffraction pattern from second pulse photograph of Si frame reconstructed picture including frame 34
VUV-FEL Pump-probe Experiments: FEL-induced Explosion with 30 fs Time Resolution Latex particles Multilayer Mirror 30 fs pulse (9 μm long) Detector Δz Prompt diffraction Delayed diffraction FLASH Single shot ultrafast time-delay X-ray hologram, with 300 fs delay Time delay = 2Δz/c The pattern is the interference of the waves scattered from the unexploded particle (reference wave) and the same particle during explosion. Many particles generate speckle also. Chapman, Hajdu and collaborators 35
VUV-FEL Pump-probe Experiments: FEL-induced Explosion with 30 fs Time Resolution Latex particles Multilayer Mirror 30 fs pulse (9 μm long) Detector Δz Prompt diffraction Delayed diffraction FLASH Single shot ultrafast time-delay X-ray hologram, with 300 fs delay Time delay = 2Δz/c The pattern is the interference of the waves scattered from the unexploded particle (reference wave) and the same particle during explosion. Many particles generate speckle also. Chapman, Hajdu and collaborators 36
New experimental domain Laser experiments Synchrotron radiation experiments The combination of two successful fields of photon research will lead to new science and innovations Accelerator Science & Particle Physics methodology 37
New experimental domain Synchrotron radiation Laser experiments X-ray FEL experiments experiments The combination of two successful fields of photon research will lead to new science and innovations Accelerator Science & Particle Physics methodology 38