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Science frontiers with the FERMI@elettra Free Electron Laser. C. Masciovecchio, F. Parmigiani Elettra Synchrotron, S.S. 14 km 163,5 – 34012 Basovizza, Trieste – Italy. FERMI@elettra DIPROI ( DIffraction & PROjection Imaging) beamline M. Kiskinova
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Science frontiers with the FERMI@elettra Free Electron Laser C. Masciovecchio, F. ParmigianiElettra Synchrotron, S.S. 14 km 163,5 – 34012 Basovizza, Trieste – Italy • FERMI@elettra • DIPROI(DIffraction & PROjection Imaging) beamlineM. Kiskinova • LDM(Low Density Matter) beamlineC. Callegari • EIS(Elastic & Inelastic Scattering) beamlineC. Masciovecchio • Conclusions
Why Free Electron Lasers ? Emitted photons (x1014) From CW (MHz) to Pulsed (kHz) sources Different Experiments and Physics ! Synch. × 1000 Time (ps)
Why Free Electron Lasers ? Time-scales of dynamic processes occurring in matter Chemical transformations Intermolecular energy transport Electron-spin dynamics Domain dynamics Diffusion e-ph/ph-ph scat Imaging with high Spatial Resolution (~ l): fixed target imaging, particle injection imaging, ….. Dynamics: four wave mixing (nanoscale), warm dense matter (uniform heating), exterme condition, .... Resonant Experiments: XANES (tunability), XMCD (polarization), chemical mapping, ……
FERMI@elettra Bunch compressor Bunch compressor Injector 95 MeV 1.5 GeV LINAC UNDULATOR05/2010 EXP HALL05/2010 EOS Seed laser(s) DS ~20 m FEL-1 (21m) M R Front ends 2 m DS Delay DS FEL-2 (38 m) Linac R2 M2 M1 R1 Beam spreader First stage Second stage x 105 The pulse in time is Transform Limited L. H. Yu et al., 91, 074801 PRL(2003)
FERMI@elettra Tunability: (fast) 5 – 20% at a given Energy Polarization: Circular V and H Beam Profile: ~ Transform Limited (10 – 1000 fs) When? FEL1 Oct 2010 switch on FEL2 Jul 2011 switch on
FERMI@elettra Sep 2009 LDM LDM Monochromator Spectrometer Shutters Planemirrors KB Systems Delay Lines 6º 2.5° FEL 1 2.5° 4º DIPROI 5° 75.1/61.1 FEL 2 2.5° EIS Switching 6º Safety Hutch I0monitors TIMEX focusing TIMER TIMEX DIPROI(DIffraction & PROjection Imaging) beamline LDM(Low Density Matter) beamline EIS(Elastic & Inelastic Scattering) beamline
Imaging Scattering DIPROI beamline M. Kiskinova H. Chapman, S. Bajt, Lars Gumprecht(DESY); A. Barty, B. Woods, M. Bogan, E. Spiller, M. Pivovaroff, A. Nelson (LLNL); U. Vogt, H. Hertz (KTH Stockholm); G. Morrison (King’s College); D. Cojoc (TASC); F. Capotondi, D. Cocco, E. Pedersoli, M. Zangrando, F. Parmigiani(Sincrotrone Trieste) Stepping into nano-world Limitations of available techniques: Scanning microscopes are limited to surfaces Transmission electron microscopes are limited in penetration (samples thinner than ~ 30 nm) X-ray crystallography reveals the 3D atomic structures, but requires crystals X-ray microscopes are limited in resolution by the optical elements, and coherence The optic-imposed resolution limitations can be overcome by image reconstruction from the measured coherent X-ray diffraction pattern of a sample
DIPROI beamline Specific element-sensitive Abrupt changes in the X-ray scattering cross section near electronic resonances: the difference in CDIs can be used for make a “chemical map” of a specific element Song et al., PRL 100, 25504, 2008 Buried Bi structures inside a Si crystalwith a pixel resolution of ~ 15 nm DPC Fe Co CoFe2O4 in mouse 3T3 fibroblast cells “ ...this imaging technique is also sensitive to chemical states via near-edge resonances and can be extended to exploit other contrast mechanisms depending on resonant transitions such as x-ray magnetic circular dichroism.......electronic orbital as well as chemical state specific imaging of magnetic materials, semiconductors, organic materials, biominerals, and biological specimens...” FeMII 3p1/2 is at ~ 53 eV
DIPROI beamline Gaps in our current understanding of effect of Nano-Objects (NOs) introduced in biological systems and vice-versa (cell targeting, drug delivery, etc) N. Lewinski et al., Small 4, 26, (2008) Today NOs production is ~ 2000 tons in 2020 will be ~ 60000 tons !! UV -Photochemistry (NOB) Oxidative damage due to catalysed generation of reactive oxygen species, ROS, (OH, O2-, H2O2) – impact on the NOs? Bond breaking and release of free radicals or molecules – impact on the NOs? H2O O2- TOF-MS OH- O2 h+ → e- e- FEL Protection Degradation ions release CCD Redox - Sample(s) Me++ H2O2 OH- catalysis Imaging to study the alteration of cell’s morphology due to the presence of NOs and determine their spatial distribution
LDM beamlineC. Callegari F. Stienkemeier, B. von Issendorff (Univ. of Freiburg); S. Stranges (University of Rome); T. Möller, C. Bostedt (TU-Berlin); U. Buck (Göttingen); K. Fauth (Univ. of Würzburg); M. Drabbels (EPFL Lausanne); M. Schmidt (Orsay); H.N. Chapman (DESY); P. Hammond (Perth); P. Decleva (Univ. of Trieste); J.M. Dyke (Univ. of Southampton); J.‐E. Rubensson, J. Nordgren (Univ. of Uppsala); K. Prince, R. Richter, D. Cocco, M. Zangrando, F. Parmigiani (Sincrotrone Trieste) Fundamental physics: • Structure of nano clusters • Ionization dynamics • Superfluidity – relaxation dynamics • Non‐linear optics • Chirality Material science: • Electronic properties of organic nanostructures • Charge transfer dynamics in heterogeneous structures • Magnetism of nanoparticles • Catalysis in nanomaterials Biochemistry: • Micro solvation of bio‐molecules Aerosol / Atmospheric chemistry: • Reactions at microscopic water interfaces
LDM beamline HEliumNanoDroplet Isolation (HENDI) will provide molecules, clusters and nanostructured complexes at ultracold temperatures. The droplets cool the embedded species to a temperature of 380 mK only vibrational ground states are populated Circular dichroismin free ultra-cold nanoparticles Magnetic particles embedded in helium droplets at low temperatures aligned by weak magnetic fields (0.1‐1 T) small pulsed solenoid The circular polarization of FERMI@elettra allows measuring the circular dichroism unique and significant information about the magnetic properties of the particles
LDM beamline Multi‐photon single and multiple ionization experiments with FERMI@elettra pulses Seeding scheme has high photon energy precision and stability facilitate multi photon experiments where resonant conditions are sought. Feasibility Cross-section is 10-50-10-53 cm2 s. We estimate count rates of 0.1 to 100 counts/sec, for a 20 mm spot. Energy: 10‐40 eV. Circular and linear polarization required. For molecules: similar requirements L.A.A. Nikolopoulos et al., J. Phys. B: At. Mol. 34 ,545 (2002)
EIS beamlineC. Masciovecchio Andrea Di Cicco, Roberto Gunnella(University of Camerino); Adriano Filipponi(University of L’Aquila); Renato Torre (LENS); Giancarlo Ruocco, TulloScopigno(University of Rome); Francesco Sette (ESRF); FilippoBencivenga, Daniele Cocco, Francesco D’Amico, RiccardoCucini, Angela Trapananti, F. Parmigiani(Sincrotrone Trieste) The Sample Side Short pulses with very high peak power Dt ~ 100 fs ; Peak Power ~ 5 GW ; E ~ 100 eV Non-equilibrium distribution of electrons What happens to the Sample? Converge (electron-electron & electron-phonon collisions) to equilibrium (Fermi-like) During this complex dynamics atoms go through a relaxation process due to the dramatic changes of the potential energy surface The intensity of the FEL pulses will determine the process to which the sample will undergo: simple heating, structural changes, ultrafast melting or ultrafast ablation TEMAX TEMAX Dt, Peak Power, E, Sample, Fluence, ….. TLMAX TLMAX TIMEX TIMER
Q (q) q 2 10 IXS BLS IUVS 1 w = cs·Q 10 BL30/21 0 10 -1 10 w (meV) = 7000 m/s INS BL10.2 V -2 10 = 500 m/s V -3 10 nano-scale macro-scale atomic-scale -4 10 -3 -2 -1 0 1 2 10 10 10 10 10 10 Q ( nm -1 ) EIS beamline - TIMER TIMER TIME-Resolved spectroscopy of mesoscopic dynamics in condensed matter Challenge: Study Collective Excitations in Disordered Systems in the Unexploredw-Q region Determination of the Dynamic Structure Factor: S(Q,w)
Why Disordered Systems ? Unsolved problems in physics • Condensed matter physics • Amorphous solids • What is the nature of the transitionbetween a fluid or regular solid and a glassy phase? What are the physical processes giving rise to the general properties of glasses? • High-temperature superconductors • What is the responsible mechanism that causes certain materials to exhibit superconductivity at temperatures much higher than around 50 Kelvin? • Sonoluminescence • What causes the emission of short bursts of light from imploding bubbles in a liquid when excited by sound? • Turbulence • Is it possible to make a theoretical model to describe the statistics of a turbulent flow (in particular, its internal structures)? Also, under what conditions do smooth solution to the Navier-Stokes equations exist? Glass is a very general state of condensed matter a large variety of systems can be transformed from liquid to glass The liquid-glass transition cannot be described in the framework of classical phase transitions since Tg depends on thequenching rate one cannot define anorder parametershowing a critical behaviour at Tg
The debate on V-SiO2 sound attenuation IXS and IUVS data in the ~ 0.1 - 1 nm-1 region for Vitreous Silica The understanding of collective dynamics nature in glasses at the nanoscale is still debated P. Benassiet al., PRL 77,3835 (1996) Existence of propagating excitations at high frequency M. Foret et al., PRL 77,3831 (1996) They are localized above ~ 1 nm-1 F. Setteet al., Science 280,1550 (1998) They are acoustic-like G. Ruocco et al., PRL 83, 5583 (1999) Change of sound attenuation mechanism at 0.1-1 nm-1 B. Ruffle´ et al., PRL 90, 095502 (2003) Change is at 1 nm-1 C. Masciovecchio et al., PRL 97,035501 (2006) Change is at 0.2 nm-1 W. Schirmacheret al., PRL 98,025501 (2007) Model agrees with Masciovecchio et al. B. Ruffle´ et al., PRL 100,015501 (2008) Shirmacher model is not correct Thermal Conductivity, Excess in the V-DoS (Boson Peak), Specific Heat
2 10 IXS BLS 1 10 IUVS 0 10 Esignal (meV) -1 10 = 7000 m/s Q(l,q) INS V w -2 10 = 500 m/s Epump V q -3 10 -4 10 -3 -2 -1 0 1 2 BRISP 10 10 10 10 10 10 Epump Q( nm -1 ) Eprobe European Research Council ERC Starting Grant Research proposal TIME-Resolved Spectroscopy of Nanoscale Dynamics in Condensed Matter Physics TIMER Funded Grant: 1.8M€Duration: 5 years Start: June 2008 Solution: Free Electron Laser basedTransient Grating Spectroscopy F(Q,t) Intermediate Scattering Function
Sample Excitation Pulses pulse qs Diffracted Probe Pulse Induced Standing Wave (Transient Grating) Splitter Delayed Probe Pulse (Phase Matching) Standing Wave Periodicity x= 2p/Q Q = 2kosinqs/2 F ( Q , t ) Density Modulation Amplitude Monitored in Time by the Probe Pulse TIMER - The Technique in Detail
F(Q,t) (a.u.) region Thermal region Sound waves region t (ps) S(Q,w) (a.u.) w (meV) The Spectrum Optical absorption Temperature Grating Time-dependent Density Response (driven by thermal expansion) S(t) ( cost – F(Q,t)) S(t) Glycerol T=205 K H2O 2 nm-1
Typical Infrared/Visible Set-Up M 1 Probing CW (or pulsed) laser beam Delay Line (only for pulsed probe) DM 2=21 Excitation pulsed laser beam Phase Control (Heterodyne) Beam stop (Homodyne) Neutral Filter (Heterodyne) Eex1 EL APD M Epr Sample DOE: Phase Mask Eex2 Es (Homodyne) EL+Es (Heterodyne) AL2 AL1 Challenge: Extend and modify the set-up for UV Transient Grating Experiments
The VUV Set-Up 1st harmonic l0 FEL pulse Grating ~5° Laminar grating (~20% in ± 1 order) ~15° Focusing mirrors 3rd harmonic (~ 2%) l1 = l0/3 ~5° ~5° CCD camera Delay line (ML mirrors, 3-meter long) TIMER ML mirrors 2qs R&D, design and prototyping (12/2009) 2qs Construction and installation (06/2010) Sample Commissioning (12/2010) User operation (06/2011)
Other Possible Experiments Heat Transport, Diffusion phenomena, Flow Studies, Concentration Grating, Electronic Energy Transfer, Photochemical Reactions, Optical Damage ……………… H. J. Eichler et al., J. Appl. Phys. 44, 5455 (1973)
Spin Dynamics TG can excite Spin Waves using orthogonal polarization Spin Diffusion and Relaxation in a 2-dim. Electron Gas
HHG in a Gas Jet The harmonic signal encodes structural information on the orbital full reconstruction “......High harmonic transient grating spectroscopy can be extended to all forms of molecular excitation and to weak resonant excitation......”
EIS beamline - TIMEX Going Extreme with TIMEX: Warm Dense Matter (WDM), ultrafast heating and melting, study of the dynamics of melting and nucleation The phase diagram of carbon is poorly understood Pioneering Femtosecond Experiment A. Ludwig, Z. Electrochem. 8, 273 (1902) D. H. Reitze et al., PRB 45, 2677 (1992) N. Bloembergen, Nature 356, 110 (1992) “Femtosecond Experiments can be improved by using probe pulses in the VUV ...... to determine individual Drude parameters....” dielectric function e Time-Resolved X-Ray Abs Spectroscopy Hypothetical phase diagram of Carbon High r liquid Diamond J. N. Glosli et al., PRL 82, 4656 (1999) “ .. mixture of the two coexisting liquid phases or in a supercritical fluid.....” Low r liquid Graphite A. Cavalleri et al., EPL 57, 281(2002) S. L. Johnson et al., PRL 94, 057407 (2005) Long Times (t > 100 ps), Tamped sample
EIS beamline - TIMEX Use the FEL Tunability to measure a XANES spectrum Detector FEL 3rdharmonic Pulsed Laser Si foil Jitter may be kept ~ 30 fs
Conclusions Beamline for Magnetism - under evaluation (F. Parmigiani) Beamline for THz Spectroscopy - under evaluation (S. Lupi)