Lecture Plan CHESS. 1. Present and Future Synchrotron X-ray X. 2. Solving the X-ray X. Phase Problem. 3. Strain Fields in Thin-film and Nanostructures

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1 Lecture Plan Qun Shen Cornell High Energy Synchrotron Source () and Department of Materials Science and Engineering Cornell University, Ithaca, New York 14853, USA 1. Present and Future Synchrotron X-ray X Sources 2. Solving the X-ray X Phase Problem 3. Strain Fields in Thin-film and Nanostructures 4. X-ray X Polarization Shen (Cornell U.) / September

2 Present and Future Synchrotron X-ray X Sources Qun Shen Cornell High Energy Synchrotron Source () and Department of Materials Science and Engineering Cornell University, Ithaca, New York 14853, USA Collaborators D. Bilderback, K. Finkelstein, E. Fontes, S. Gruner, R. Headrick, A. Kazimirov, D. Smilgies, C.-S. Zha Cornell High Energy Synchrotron Source, Cornell University I. Bazarov, H. Padamsee, R. Talman, M. Tigner, Laboratory for Nuclear Studies, Cornell University G. Krafft, L. Merminga, C. Sinclair, Thomas Jefferson National Accelerator Facility Shen (Cornell U.) / September

3 Outline Synchrotron radiation worldwide Basic parameters facility at Cornell Science examples Limitations of storage-rings Future synchrotron source proposals X-ray Free Electron Laser (XFEL) Energy Recovery Linac (ERL) New science potentials Future plan and prospects Shen (Cornell U.) / September

4 Synchrotron Facilities ~ 70 storage-ring ring based synchrotron facilities worldwide A.Hopkirk at Daresbury Laboratory, UK, Shen (Cornell U.) / September

5 Source Emittance and Brilliance Phase-space space Emittance: EM wave: E(r, t) = E 0 e i(k r ωt) x x Integrated total flux F n x ε x = σ x σ x σ x y ε y = σ y σ y σ y σ E E ε τ = σ τ σ E / E σ x x σ y y σ τ t Brilliance: : photon flux density in phase-space space Average B = F n (2π) 2 ε x ε y Peak B ^ = F n (2π) 3 ε x ε y ε τ Shen (Cornell U.) / September

6 Tesla X-ray Curves (from March 2001 Technical Design Report) ERL ERL ERL data points added from Qun Shen s 2001 technical report Shen (Cornell U.) / September

7 Growth in Synchrotron Radiation Science INSPEC: Synchrotron Radiation (not astronomy) Protein Data Bank: Deposits / year Number of Publications Number of PDB Deposits Shen (Cornell U.) / September

8 Facility Example: ESRF European Synchrotron Radiation Facility (ESRF). Web site: Shen (Cornell U.) / September

9 ESRF Beam Time Usage Shen (Cornell U.) / September

10 Cornell High Energy Synchrotron Source Cornell University Ithaca, New York 6 beam lines, 12 stations 8 scientists, 19 support staff NSF funding $3M /year Mac $1.8M /yr NIH No CATs / PRTs Cornell G-line Shen (Cornell U.) / September

11 High X-ray X Flux from Wigglers G-line Wiggler: designed & fabricated in house by K.D. Finkelstein at Shen (Cornell U.) / September

12 X-ray Interactions with Matter E absorption spectroscopy e E, k scattering elastic E =E inelastic E E E, k x-rays I 0 I Shen (Cornell U.) / September

13 Structural Biology Yonath et al, Weizmann Inst., Israel (2000) MacKinnon et al., Rockefeller U. (1998, 2000) Shen (Cornell U.) / September

14 Real-time Crystal Growth Ion-assisted MOCVD growth of GaN on sapphire. Headrick et al., PRB 58, 4818 (1998) Shen (Cornell U.) / September

15 Time-Resolved X-ray X Imaging X-ray Fuel injector PAD Wang et al. (APS, 2001) Gruner et al. () Imaging of diesel fuel spray With µs s time resolution Pixel Array Detector (PAD) Liquid-gas mixture core Ultrasonic shock wave Near-nozzle region imaging Shen (Cornell U.) / September

16 High Pressure Science Bassett et al. (Cornell) m Fe(III)Cl 3 / H 2 O 1.5 I f /I o T = 400 C P = 60 MPa Energy (ev) Mao et al. (Geophys. Lab) Zha et al. () Shen (Cornell U.) / September

17 Industrial Usage LLNL, Sandia, ALS, Intel, Motorola, AMD, Micron, Infineon & IBM (April 2001) EUV Interferometer at Beamline at ALS λ = 13.4 nm Current lithography technology is expected to allow semiconductor manufacturers to eventually print circuits as small as 0.1 µm in width. EUV lithography technology is being developed to allow manufacturers to print circuit lines down to < 0.03 µm, extending the current pace of semiconductor innovation at least through the end of this decade. Processors built using EUV technology are expected to reach up to 10 GHz in By comparison, the fastest Pentium-4 processor today is 1.5 GHz. Shen (Cornell U.) / September

18 Storage Ring Sources APS SPring-8 ESRF Mature and well-understood Equilibrium of stored beam in entire ring Each electron bunch ~ 10,000 turns to reach equilibrium Emission of synchrotron radiation Perturbations on electron trajectories Limits on energy spread, horizontal emittance, bunch length Shen (Cornell U.) / September

19 New Synchrotron Sources Question: Are there alternatives to storage-ring ring based sources? Proposed new sources: Ultimate storage ring light source: USRLS X-ray free electron lasers (XFEL): LCLS, TESLA Energy recovery linac (ERL): Cornell, BNL, ALS,... From users perspective: High intensity & brilliance Beam is there all the time, without decay in current High degree of 2D transverse coherence Ultra-short x-ray pulses Flexible source operation to meet specific needs Shen (Cornell U.) / September

20 X-ray Free Electron Laser Self Amplified Spontaneous Emission (SASE) TESLA Technical Design Report (2001). Shen (Cornell U.) / September

21 Slide from John Galayda (SLAC) (LCLS Project Manager) LINACINAC COHERENT LIGHTIGHT SOURCEOURCE I-280 Sand Hill Rd Shen (Cornell U.) / September

22 Tesla XFEL Project (DESY, Germany) TESLA Technical Design Report (2001). Shen (Cornell U.) / September

23 Single Pass Device Single-pass non-equilibrium device Low emittance and short pulses from injector can be preserved Ultra-small round beam Potential for ultra-high brilliance Electron bunches dumped after single pass Difficult to maintain high current Enormous power bill Not economical or practical Shen (Cornell U.) / September

24 Energy Recovery Linac Injector: high-brilliance electron bunches generated by fs laser on photocathode are accelerated to ~10MeV M. Tigner, Nuovo Cimento 37, 1228 (1965) Main Linac: superconducting cells accelerate electron bunches to 5-7 GeV, and recover energy from returning bunches (180 o out of phase) Transport loop: produces high-brilliance x-ray beams through undulators, and reinjects electrons into main linac for energy recovery Accelerating bunch Returning bunch m Shen (Cornell U.) / September

25 ERL Concept Works! 48 MeV 5 ma Average IR Power 1720 W Average current 5 ma Electron energy 48 MeV Wavelength range µm Charge per pulse >60 pc Pulse length ps Repetition frequency up to MHz Energy recovery efficiency 99.97% Shen (Cornell U.) / September

26 Basic Comparison on Machine Issues ERL and XFEL ERL XFEL linac driven undulator linac driven long undulator low bunch charge single pass high bunch charge single pass energy recycled self-amplified spont. emission high rep-rate low rep-rate simultaneous beamlines multiplexed beamlines m Shen (Cornell U.) / September

27 Basic Comparison on Machine Issues ERL and Storage Rings Storage Ring stored-beam + undulator low bunch charge multi pass energy stored high rep-rate simultaneous beamlines ERL linac driven undulator low bunch charge single pass energy recycled high rep-rate simultaneous beamlines ESRF m Shen (Cornell U.) / September

28 Activities at Cornell on ERL February 11, 2000 ERL proposed, by Tigner to advisory board June-July 2000 White Paper on ERL, by Gruner, Bilderback, Tigner August 11-12, 2000 Machine physics workshop on ERL December 2-3, 2000 X-ray science workshop on ERL July 6, 2001 Proposal of ERL Phase-I, submitted to NSF August 21, 2001 Workshop on ERL at SRI 2001, organized by Bilderback & Gruner (), Kao (BNL) and Williams (TJNAF) ERL website: Shen (Cornell U.) / September

29 Preliminary Design Parameters of ERL ERL high-flux ERL high-coherence Machine design Insertion device Energy E G (GeV) Current I (ma) Charge q (nc/bunch) ε x (nm-rad) ε y (nm-rad) Bunch fwhm τ (ps) # of bunches f (Hz) Undulator L (m) Period λ u (cm) # of period N u Horizontal β x (m) Vertical β y (m) Undulator E st harmonic E 1 (kev) Shen (Cornell U.) / September

30 ERL: Expected Performance Average Brilliance (ph/s/0.1%/mm 2 /mr 2 ) LCLS SASE Sp8 25m APS 4.8m APS 2.4m LCLS spont. ERL 25m 0.015nm 10mA Sp8 5m ESRF U35 24p wiggler 0.15nm 100mA 49p wiggler Peak Brilliance (ph/s/0.1%/mm 2 /mr 2 ) nm 100mA 4.7ps Sp8 25m ESRF U35 49-pole G/A-wiggler τ=153ps, f=17.6mhz (9x5) 24-pole F-wiggler ERL 25m 0.015nm 10mA 0.3ps Sp8 5m APS 2.4m 0.15nm 100mA 0.3ps Photon Energy (kev) Photon Energy (kev) Shen (Cornell U.) / September

31 ERL: Expected Performance Coherent Fraction 10 0 LCLS SASE APS 4.8m ESRF U35 ERL 25m 0.015nm 10mA ERL 25m 0.15nm 100mA APS 2.4m 25m Sp8 5m Peak Photon Degeneracy Parameter nm 100mA APS 4.8m ESRF U35 Sp8 25m Sp8 5m ERL 25m 0.015nm 10mA APS 2.4m Photon Energy (kev) Photon Energy (kev) Shen (Cornell U.) / September

32 ERL: Source Size and Pulse Length ESRF ma ε x = 4 nm mrad ε y = 0.01 nm mrad B = ph/s/mm 2 /mrad 2 /0.1%BW L ID = 5 m ERL / 10 ma ε x = ε y = 0.2 / 0.02 nm mrad B = ph/s/mm 2 /mrad 2 /0.1%BW B = ph/s/mm 2 /mrad 2 /0.1%BW L ID = 25 m ERL (w/ compression) ERL (no compression) ESRF t Shen (Cornell U.) / September

33 Power / Heat Loads ERL 5.3GeV SPring-8 8 GeV ID length 25 m 25 m 25 m 4.5 m Beam current 100 ma 10 ma 100 ma 100 ma Total ave. power 33.9 kw 3.4 kw 31.2 kw 15.7 kw 20m 2600 W/mm W/mm W/mm W/mm 2 Peak power 86.9 MW 8.7 MW 2.5 MW 1.3 MW 15 GeV 25 GeV ID length 100 m 87 m Beam current µa 63 µa Total ave. power 3 W 1.6 kw 20m 63 W/mm kw/mm 2 Peak power 9 GW 60 GW Shen (Cornell U.) / September

34 ERL Beam Lines ERL beam lines are similar to 3rd SR such as Spring-8 TESLA Shen (Cornell U.) / September

35 Basic Properties of ERL Low e-beam emittance Small round beams Short sub-ps x-ray pulses Beamlines similar to 3rd SR High repetition rate Flexible operation ERL allows: Exploration of new sciences that are not possible at existing sources Accommodation of existing experiments with substantial improvements Shen (Cornell U.) / September

36 X-ray Science Workshop with ERL Cornell University, Ithaca, New York December 2-3, ERL Overview: Sol Gruner, Cornell Univ. 2. ERL Machine Opportunities: Maury Tigner, Cornell U. 3. ERL X-ray Opportunities: Don Bilderback, Cornell U. 4. ERL Insertion Device Design Considerations: Pascal Elleaume, ESRF 5. Coherent X-ray Microscopy: Chris Jacobson & Janos Kirz, U. Copenhagen 6. Sources of Coherent X-rays: synchrotorns, ERLs, EFELs: John Arthur, SSRL 7. Collective Dynamics by High Resolution Inelastic X-ray Scattering Spectroscopy: Sow-Hsin Chen, MIT 8. X-ray Photon Correlation Spectroscopy: Steve Dierker, U. Michigan 9. Localized Vibrational and Spin Wave Modes in Nonlinear Periodic Lattices: Al Sievers, Cornell U. 10. Condensed Matter Research at high Pressure: Beyond 3rd Generation Facilities: John Parise, SUNY Stony Brook 11. Probing Polycrystals with Microfocused High-Energy X-rays: Bob Suter, Carnegie Mellon 12. Structural and Electronic Studies in the Time Domain: Phil Heimann, ALS 13. Atomic-to-macro Structure and Evolution with Shorter Pulses and Higher Brilliance X-ray Beams: Ben Larson, ORNL 14. Frontiers of X-ray Microdiffraction: Gene Ice, ORNL 15. Microfluorescence, Microspectroscopy and Microtomography Application: Mark Rivers, U. Chicago 16. ERL Opportunities Employing Crystal Optics: Al Macrander, APS 17. Intensity Fluctuation Spectroscopy using Coherent X-rays: Mark Sutton, McGill, Joel Brock, Cornell U. 18. How an ERL Might Benefit Our Understanding of Elementary Excitations in Condensed Matter: Ercan Alp, APS 19. Monitor Ion Beam and Ion-Solid Structure Monitoring: Richard Matyi, NIST 20. Exploring Some Frontiers of ERL Machine: Ivan Bazarov, Cornell U. 21. Vertically Polarized Undulators: Jens Als-Nielson, U. Copenhagen 22. ERL machine for NSLS: Peter Siddons, BNL 23. Go to Double Undulator for 2X brilliance: John Galayda, ANL 24. Comparison of Storage Rings, ERL, & XFEL x-ray sources: Gopal Shenoy & John Arthur nm diameter x-ray beams with glass capillary: Don Bilderback, Cornell U. 26. ERL Timing & CEBAF Overview: Geoff Kraft, Jefferson National Laboratory 27. Summary of ERL Beamline Needs Shen (Cornell U.) / September

37 X-ray Science at ERL All brilliance-driven experiments that require a large number of photons per phase-space volume: x, θ x, y, θ y, t, E Brilliance: : micro-beam, inelastic scattering Coherence: : XPCS, coherent scattering Ultra-fast fast: : scattering, XAS Shen (Cornell U.) / September

38 X-ray Science at ERL: Improved Micro-beam / µ-probe: x Larson (2000) Bilderback (2000), ERL Workshop Shen (Cornell U.) / September

39 X-ray Science at ERL: Improved photon-correlation spectroscopy: θ x, t Dierker (2000), ERL Workshop Shen (Cornell U.) / September

40 X-ray Science at ERL: Improved Time-resolved x-ray x studies: t Larson (2000) ERL Workshop Shen (Cornell U.) / September

41 X-ray Science at ERL: New parameters in new regimes Peak 8 kev (ph/s/0.1%/mm 2 /mr 2 ) rd SR APS upg 49p 24p Sp8-25m 2nd SR ESRF APS ERL 0.015nm 0.01A 0.15nm 0.1A 0.15nm 0.1A 4.7ps 1.5nm 0.1A ALS fs BLs ALS sect.6 undulator ALS Ultra-fast pump-probe probe studies: σ τ = 100 fs, f = MHz GHz Techert, Schott, Wulff, PRL 86, 2030 (2001). Time resolved XRD at ESRF, resolution 10 ps X-ray Pulse Duration τ (ps) Shen (Cornell U.) / September

42 X-ray Science at ERL: New parameters in new regimes Peak Coherent Electric Field (V/m) strong-field regime perturbative nonlinear regime linear regime CO 2 Gas lasers Nd: Glass Ruby Terawatt Ti: Al 2 O 3 electron binding field in atoms Excimers Higher Harmonics Generation Tunable dye lasers TESLA XFEL LCLS XFEL atmospheric E-field at earth surface ERL 0.015nm 0.15nm ESRF APS ALS Sp-8 wigglers Nonlinear condensed matter: coherent E-field E > 10 7 V/m degeneracy parameter ~ photon absorption? Photon Energy (ev) Shen (Cornell U.) / September

43 Proposed Timeline at Cornell ERL ERL Phase-I FY02 Phase-I proposal (July 01) Phase-I ERL 100MeV 100mA FY06 Phase-II ERL ERL Phase-II 2010 Phase-II ERL operation Shen (Cornell U.) / September

44 Phase-I I ERL Beam Energy Injection Energy Beam current 100 MeV 5 MeV 100 ma Charge per bunch 77 pc Rms Emittance, norm. 2 µm Shortest bunch length 100 fs Perspective view of the injector TTF 9-cell 1.3 GHz niobium cavity (courtesy of DESY) (Q 0 ~ MV/m) Systems, Inc. Energy Advanced Shen (Cornell U.) / September

45 Phase-II ERL Parameter Value Unit Beam Energy 5-7 GeV Average Current 100 / 10 ma Fundamental frequency 1.3 GHz Charge per bunch 77 / 8 pc Injection Energy 10 MeV Normalized emittance 2 / 0.2* µm Energy spread % Bunch length in IDs 0.1-2* ps Total radiated power 400 kw Shen (Cornell U.) / September

46 Brilliance Preserving Optics: micro-focusing Bilderback (2000) ERL Workshop D 1 D 2 Sigma x Sigma x Sigma y Sigma y (µm) (µr) (µm) (µr) ESRF Microfocus BL Advanced Photon Source Energy Recovery Linac nm, 100 ma, 25 m ID Energy Recovery Linac nm, 10 ma, 2 m ID Require slope error δθ << σ x / D 1 = 3.9 µm / 40 m = 0.1 µrad Shen (Cornell U.) / September

47 Phase-II ERL Optics Challenges Κ high-heat-load capable Κ brilliance preserving to provide high transverse coherence Κ optics to manipulate, preserve and produce short pulses Freund (2001), used by Hastings & Tschentscher, in TESLA Technical Design Report, ed. Materlik & Tschentscher (DESY, Hamburg) Shen (Cornell U.) / September

48 Pulse-length length Manipulation Zholents, et al. (1999) NIM A425, Shen (Cornell U.) / September

49 Conclusions Synchrotron Radiation: rapidly growing branch of science & technology serves a diverse user base from basic to industrial all based on storage-rings limitation of storage-rings => future XFEL, ERL Energy Recovery Linac (ERL) would offer: exciting alternative to storage-ring & XFEL sources x-ray beam quality superior to storage-rings accommodation of both new and existing expts. similarities in beamline design and cost-effectiveness ERL would be complementary to XFELs possibility of upgrading all storage-rings Shen (Cornell U.) / September

50 The End Shen (Cornell U.) / September