1. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 1 X-ray Pump-Probe Instrument David Fritz Instrument Overview Instrument Layout System Description X-ray Optics &Diagnostics Sample Environments Detectors Laser System FEL/Pump Laser Timing System Technical Issues Summary Instrument Overview Instrument Layout System Description X-ray Optics &Diagnostics Sample Environments Detectors Laser System FEL/Pump Laser Timing System Technical Issues Summary

2. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 2 X-ray Pump-Probe Science Phase Transitions Order / Disorder Metal/Insulator Phonon Dynamics Charge Transfer Reactions Photosynthesis Photovoltaics Vision Photoactive Proteins Phase Transitions Order / Disorder Metal/Insulator Phonon Dynamics Charge Transfer Reactions Photosynthesis Photovoltaics Vision Photoactive Proteins photo- excitation Stampfli and Bennemann Phys. Rev. B 49, 7299 (1994) photo- excitation

3. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 3 Ultrafast Hard X-ray Sources to Date 3 rd Generation Synchrotrons (APS) ~ 1 x 10 9 photons/second coincident with a 1 kHz Laser 100 ps pulse duration Slicing Source ~ 1 x 10 6 photons/second coincident with a 1 kHz Laser 100 fs pulse duration Laser Plasma Source ~ 1 x 10 5 photons/second collected at 10 Hz 300 fs pulse duration Sub-Picosecond Pulse Source ~ 1 x 10 7 photons/second coincident with a 10 Hz Laser 100 fs pulse duration 3 rd Generation Synchrotrons (APS) ~ 1 x 10 9 photons/second coincident with a 1 kHz Laser 100 ps pulse duration Slicing Source ~ 1 x 10 6 photons/second coincident with a 1 kHz Laser 100 fs pulse duration Laser Plasma Source ~ 1 x 10 5 photons/second collected at 10 Hz 300 fs pulse duration Sub-Picosecond Pulse Source ~ 1 x 10 7 photons/second coincident with a 10 Hz Laser 100 fs pulse duration

4. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 4 Ultrafast X-ray Science to Date Limited to slow processes ( > 100 ps) or X-ray diffraction from single crystals Limited to slow processes ( > 100 ps) or X-ray diffraction from single crystals Large Amplitude Coherent Phonons Non-thermal Melting of Semiconductors 20 minute acquisition at SPPSSingle Shot at SPPS

5. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 5 XPP Instrument Scope X-ray Wavelength and BandwidthSample EnvironmentScattering TechniqueExcitation Laser Parameters  Fundamental  Monochromatic Fundamental  3 rd Harmonic  Monochromatic 3 rd Harmonic  Room Press. & Room Temp  Temperature Controlled Cryostat  Liquid  Vacuum  Wide Angle Scattering  Small Angle Scattering  Emission Med. Energy (2 mJ fund.)  Fundamental (800 nm)  2 nd Harmonic (400 nm)  3 rd Harmonic (266 nm)  OPA High Energy (20 mJ fund.)  Fundamental (800 nm)  2 nd Harmonic (400 nm)  3 rd Harmonic (266 nm) Versatility is key to the instrument success Instrument will operate in the 6-25 keV photon energy range

6. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 6 Instrument Specifications Secondary Slits Wide Angle Stage Small Angle Stage Photon Shutter Focusing Lenses Photon Shutter Monochromator Photon Shutter ItemPurposeSpecification Large Offset Monochromator Multiplex FEL radiation, Narrow FEL spectrum 600 mm offset, ≤ 10 -4 spectral bandwidth Harmonic Rejection Mirrors Filter 3 rd Harmonic Radiation 10 5 : 1 contrast ratio < 0.5 nm surface roughness Slits/Apertures Beam definition, Beam halo cleaning 0.1 um stability, 1 um repeatability Attenuators Control incident x-ray flux Variable, up to 10 7 reduction at 1.5 Å Diagnostics Intensity Monitor, Position Monitor 0.1% relative intensity measurement, < 5% incident x-ray attenuation Be Focusing Lenses Increase incident x-ray flux 2-10 mm, 40-60 mm spot size at 1.5 Å, 2-10 mm spot size at 0.5 Å Laser SystemPhotoexcitation of samples Ultrafast pulse duration (<50 fs), Up to 20 mJ pulse energy at 800 nm, 120 Hz X-ray Diffractometer Sample orientation Kappa diffractometer, Platform diffractometer Wide Angle Detector Stage Move the detector in reciprocal space Spherical detector motion at a 10-150 cm radius Small Angle Detector Stage Collect SAXS patterns 2.5, 5, and 10 m Sample-to-detector distance, 0.5 m horizontal detector motion 2D Detector Provide 2D pixelated detection capability 1024 x1024 pixels, 120 Hz frame/s, dynamic range >10 3, single-photon sensitivity, pixel size 90x90 mm 2 Mirror System Primary Slits Diagnostics Attenuators Diagnostics Diffractometer NEH Hutch 3 Diagnostics Laser Port FEE Diagnostics

7. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 7 XPP Instrument Location XCS AMO (LCLS) CXI XPP Endstation

8. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 8 X-ray Pump-Probe Instrument Offset Monochromator Laser System (Fundamental) X-ray Diffractometer & BNL Detector Wavelength Conversion Small Angle Scattering X-ray Optics and Diagnostics

9. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 9 X-ray Optics – Offset Monochromator Double crystal offset monochromator Narrows x-ray spectrum for resonant scattering experiments Multiplexes LCLS beam (mono. beam, diagnostic beam) Double crystal offset monochromator Narrows x-ray spectrum for resonant scattering experiments Multiplexes LCLS beam (mono. beam, diagnostic beam) ParameterValue Energy Range6 – 24 keV Horizontal Offset600 mm Scattering Angle14 0 - 50 0  Accuracy 0.02 arcsec χ Accuracy4 arcsec Scattering Angles (2 theta) 1.5 Å0.5 Å Silicon 11127.6°- Silicon 22045.8°14.9° Diamond 11142.5°13.9° Diamond 220-22.8°

10. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 10 X-ray Optics - Attenuators Attenuators Variable, up to 10 7 reduction at 8.3 keV Coherence preserving High damage threshold Attenuators Variable, up to 10 7 reduction at 8.3 keV Coherence preserving High damage threshold

11. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 11 X-ray Optics – Slit Systems Slit systems Variable horizontal and vertical gap from 5 μm – 5 mm Can withstand full LCLS flux – unfocused Minimize background scatter from blades Slit systems Variable horizontal and vertical gap from 5 μm – 5 mm Can withstand full LCLS flux – unfocused Minimize background scatter from blades D. Le Bolloc’h et al., J. Synchrotron Rad., 9, 258-265 (2002).

12. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 12 X-ray Optics - Be Focusing Lenses Beryllium CRL > 40% throughput Positioning resolution and repeatability to 1 µm Z translation to vary spot size Beryllium CRL > 40% throughput Positioning resolution and repeatability to 1 µm Z translation to vary spot size B. Lengeler et al., J. Synchrotron Rad., 6, 1153-1167 (1999).

13. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 13 X-ray Optics – Harmonic Rejection Mirrors Harmonic Rejection Mirror System > 80% throughput 10 5 : 1 contrast ratio (10 7 : 1 overall) Harmonic Rejection Mirror System > 80% throughput 10 5 : 1 contrast ratio (10 7 : 1 overall) 10 -4 10 -5 10 -2 10 -6 10 -3

14. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 14 Kappa Diffractometer Kappa X-ray Diffractometer Operate in both direct and monochromatic beam Large reciprocal space access Gas stream temperature control Kappa X-ray Diffractometer Operate in both direct and monochromatic beam Large reciprocal space access Gas stream temperature control ηφ κ α = 50º Kinematic Mount XY Table μ ν δx

15. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 15 Platform Diffractometer Platform X-ray Diffractometer Operate in both direct and monochromatic beam Accommodates large sample environments (Cryostats, vacuum chambers, etc…) Platform X-ray Diffractometer Operate in both direct and monochromatic beam Accommodates large sample environments (Cryostats, vacuum chambers, etc…) χ x trans ω z trans y trans Kinematic Mount XY Table μ ν δ

16. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 16 Emission Spectroscopy X-ray Emission Spectrometer ~ 50 eV dynamic range ~ 0.1 eV resolution Large collection solid angle X-ray Emission Spectrometer ~ 50 eV dynamic range ~ 0.1 eV resolution Large collection solid angle XAMPS XY Table μ ν δ sample PSD analyzers vertical cut top view beam analyzers spectrum

17. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 17 Small Angle Scattering SAXS Capability 2.5, 5, and 10 m sample-to-detector distance 10 µrad angular resolution with XAMPS detector (10 m) Operate in both direct and monochromatic beam SAXS Capability 2.5, 5, and 10 m sample-to-detector distance 10 µrad angular resolution with XAMPS detector (10 m) Operate in both direct and monochromatic beam

18. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 18 2D Detectors 2D detector (BNL) 1024 x 1024 pixels 90 micron pixel size High Detector Quantum Efficiency (DQE) 10 4 dynamic range at 8 keV 120 Hz Readout Rate 2D detector (BNL) 1024 x 1024 pixels 90 micron pixel size High Detector Quantum Efficiency (DQE) 10 4 dynamic range at 8 keV 120 Hz Readout Rate

19. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 19 Laser System

20. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 20 Laser System Ti:Sapphire Oscillator & Power Amplifiers Compressor, OPA, Harmonic Generation, Delay Stage

21. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 21 Laser System Laser Diagnostics Temporal and spectral characterization Grenouille – Real time pulse duration, spectrum 3 rd Order Correlator – Contrast ratio Energy characterization Per pulse Joule meter, 120 Hz, 1% accuracy Spatial characterization Profile monitor at a “virtual” sample, 5 μ m resolution Laser Diagnostics Temporal and spectral characterization Grenouille – Real time pulse duration, spectrum 3 rd Order Correlator – Contrast ratio Energy characterization Per pulse Joule meter, 120 Hz, 1% accuracy Spatial characterization Profile monitor at a “virtual” sample, 5 μ m resolution

22. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 22 X-ray Diagnostics Transmissive Intensity Monitor > 95 % Transmission Relative accuracy < 0.1% Flourescent Screeens Diodes Transmissive Intensity Monitor > 95 % Transmission Relative accuracy < 0.1% Flourescent Screeens Diodes

23. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 23 Accelerating Elements Experimental Pump Laser Electron Gun Master Clock RF Distribution Network Laser/FEL Timing Sources of Short Term Jitter E-beam phase to RF phase jitter Electron beam energy jitter + dispersive electron optics End station laser phase to RF Phase ~ 1 ps limit Sources of Short Term Jitter E-beam phase to RF phase jitter Electron beam energy jitter + dispersive electron optics End station laser phase to RF Phase ~ 1 ps limit

24. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 24 Traditional Pump-probe Delay will be achieved by optical delay and/or RF phase shift Resolution limited by LCLS/laser jitter ~ 1 ps limit Delay will be achieved by optical delay and/or RF phase shift Resolution limited by LCLS/laser jitter ~ 1 ps limit C. W. Siders

25. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 25 Single Shot Pump-Probe time (fs) diffracted intensity Limited to X-ray diffraction Need ‘large’ effects Imaging resolution affects temporal resolution Limited to X-ray diffraction Need ‘large’ effects Imaging resolution affects temporal resolution A. M. Lindenberg et al., Science, 308, 392 (2005).

26. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 26 Laser/FEL Timing Electro-optic Sampling Laser Pump-probe Laser LTUNEH Gun Laser Sector 20 Stabilized Fiber Optic RF Distribution (10 fs) LBNL Electro-optic Sampling Enhanced Temporal Resolution (~ 100 fs) Limited by our ability to phase lock the lasers to the RF backbone Limited by Intra-bunch SASE jitter Electro-optic Sampling Enhanced Temporal Resolution (~ 100 fs) Limited by our ability to phase lock the lasers to the RF backbone Limited by Intra-bunch SASE jitter

27. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 27 Non-sequential Sampling 100 consecutive shots Single shot, Lorentzian fit Diagnostic required to measure LCLS/laser timing EOS demonstrated at SPPS Diagnostic required to measure LCLS/laser timing EOS demonstrated at SPPS

28. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 28 Laser/FEL Timing Diagnostic Beam for Direct Timing Measurement Permits destructive x-ray timing measurement in hutch Same excitation laser can be used Diagnostic Beam for Direct Timing Measurement Permits destructive x-ray timing measurement in hutch Same excitation laser can be used 600mm Transmitted Beam 85% 8keV Diagnostic Beam 1.3% Mono. Beam 2.5%

29. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 29 Technical Issues 1. X-ray/Laser Timing Below 100 fs 2. Flexible Diffractometer Design - Kappa + Platform 3. Thin Monochromator Crystals - Diamond vs. Thin Silicon - (Absorption, Damage vs. Quality) 4. Monochromator Precision Motion - 200 nRad motion & stability 5. Rejecting Fundamental in 3 rd Harmonic Operation 1. X-ray/Laser Timing Below 100 fs 2. Flexible Diffractometer Design - Kappa + Platform 3. Thin Monochromator Crystals - Diamond vs. Thin Silicon - (Absorption, Damage vs. Quality) 4. Monochromator Precision Motion - 200 nRad motion & stability 5. Rejecting Fundamental in 3 rd Harmonic Operation

30. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 30 Summary Instrument design emphasizes flexibility X-ray scattering techniques WAXS SAXS Emission spectroscopy X-ray optics can tailor FEL parameters for users Many sample environments are accommodated Vacuum Low temperature (cryostat, cryostream) Samples in solution Versatile laser system Instrument design emphasizes flexibility X-ray scattering techniques WAXS SAXS Emission spectroscopy X-ray optics can tailor FEL parameters for users Many sample environments are accommodated Vacuum Low temperature (cryostat, cryostream) Samples in solution Versatile laser system

31. David Fritz dmfritz@slac.stanford.edu LCLS FAC Meeting Oct. 30, 2007 31 Non-sequential Sampling D. M. Fritz et al., Science, 315, 633 (2007). A. L. Cavalieri et al., Phys. Rev. Lett., 94, 114801 (2005).