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TERASPARC: Terahertz Radiation @ the Free-Electron Laser

TERASPARC: Terahertz Radiation @ the Free-Electron Laser. Stefano Lupi ( on behalf of the TERASPARC team) Dipartimento di Fisica, Sapienza Università di Roma and INFN. Acknowledgments. TERASPARC collaboration:

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TERASPARC: Terahertz Radiation @ the Free-Electron Laser

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  1. TERASPARC: Terahertz Radiation @ the Free-Electron Laser Stefano Lupi (on behalf of the TERASPARC team) Dipartimento di Fisica, Sapienza Università di Roma and INFN

  2. Acknowledgments TERASPARC collaboration: INFN LNF/Roma1-2: M. Bellaveglia, E. Chiadroni, P. Calvani, M. Castellano, A.Cianchi, L. Cultrera, G. Di Pirro, M. Ferrario, L. Ficcadenti, G. Gatti, O.Limaj, B. Marchetti, A. Mostacci, E. Pace, A. R. Rossi, L. Palumbo, C. Vaccarezza, and the technical staff: F. Anelli, S. Fioravanti, R. Sorchetti; INFN Torino-Catania:G. Ghigo, R. Gerbaldo, L. Gozzelino, F. Laviano ELETTRA: A. Perucchi LFN-CNR: M. Ortolani

  3. The Terahertz gap 0.1 THz – 5 THz Vanishing thermal power, few tunable and pulsed lasers. No electronics, few microwaves generators

  4. THz Science and Technology Life Sciences Condensed Matter Physics Macromolecules conformation Secondary and tertiary structure Coherent dynamic development Imaging 3D tomography of dry tissues Near-field sub-wavelenght spatial resolution SuperconductivityEnergy gapSymmetry of the order parameterDirect determination of the superfluid density Dynamics of Cooper pairs Low-dimensional materials Dimensionality crossoverNon-Fermi liquid normal statesBroken symmetry ground states Coherent Phase TransitionsPolaronsStructural Phase Transitions Magnetic sub-ps Dynamics New Technologies THz technologies Array THz detectors Metamaterials Medical diagnostic Skin cancer detection Industrial production Material inspection Production line monitoring Defense industry/Homeland security Detection of explosives and biohazards Physical and Analytical Chemistry Polar liquids Hydrogen bond Van der Waals interactions Acoustic-Optic phonon mixing in water Solutions Static and dynamic interactions between solvated ions and solvent

  5. Available THz sources Terahertz Lasers • Quantum Cascade Lasers (>1 THz); • Si- and Ge-lasers (>1.5 THz); • Gas-based lasers (emission only at some given frequencies); Sources based on electron bunch acceleration Narrow Band • Stanford (>3 THz); • Far-Infrared FELs: FELIX, FELBE; • ENEA compact FEL; • Far-IR undulator @ FLASH (Hamburg); • Backward-wave oscillators; Broad Band • Laser Amplifiers: plasma and no linear crystals (no user facility), • Coherent Synchrotron Radiation @ III Generation Machines FEL-based Broad Band (femto-second pulsed) THz Sources

  6. Coherent THz Radiation

  7. Key points for THz coherent emission Sub-ps e-bunches:X-UV-VIS FEL machines routinely produce sub-ps e-bunches.Those bunches emit coherent THz and far-IR radiation and also useful IR-VIS radiation

  8. SPARC OVERVIEW Diagnostic and Matching

  9. Performances Achieved E. Chiadroni et al, Unpublished

  10. THz-Dream THz coherent emission covering a large spectral range: 0.1 to 30 THz; THz pulse duration lower than 50 fs; Energy/pulse in the 10-100 mJ range; Far-IR, Mid-IR and VIS probe; Optical coupling between the laser and the THz pulse: THz pump-X probe;

  11. THz Experiments Average Energy (Power)Frequency-Domain Spectroscopy High Energy/Pulse THz Pump- THz Probe non-linear time-domainexperiments(THz Pump and IR+VIS Probes using IR+VIS emissions)

  12. Ultrashort, intense (E>1 MV/cm)THz pulses needed! High E field associated to the THz pulse • The high E (~MV) THz field may induce currents exceeding the critical superconducting current (breaking the Superconducting State with an Electric Field) • New kind of transient excitations (out-of-equilibrium supercurrent) avoiding heating effects; • How this no-linear state recorces to equilibrium? Ec critical field for the SC Superconducting film, T < Tc

  13. Magnetic Dynamics with THz pulses A sub-ps THz pulse associates to an E field of 1 MV/cm a B field ~ 0.5 T THz induced magnetic transitions THz Time Resolved Electron Spin Resonance

  14. Dynamical evolution from disordered conformational states to ordering Large pump THz E field may coherent induce conformational ordering and THz probe may measure its temporal evolution Conformational Collective modes of macromolecules water Conformational dynamics of DNA, proteins, lipids, result in collective THz modes. Structural changes are critically important in biological activity thus, if these modes are frozen out, the ability to change structure is lost.

  15. THz is sensitive to interaction time between a molecule and the surrounding solvent on sub-ps scale Standard high-frequency time-resolved experiments: excite in the UV-VIS a soluted molecule -----> probe in the THz the dynamical effects on solvent Femto-Chemistry High THz fields may induce molecular orientational motion or interionic motion leading to changes in local structures of solvent. This may coherent induce chemical reactions that can be measure with a VIS-UV probe.

  16. Imaging vs Penetration

  17. Chemical Pharmaceutic recognition Background absorption

  18. Imaging of Bio-materials, molecular in-vivo imaging of pathogenesis T. Lffler et al, Optics Express 9, 616 (2001) Ferguson et al, Nature Materials1, 26 (2002) X.-C Zhang Phys. Med. Biol. 47, 3667 (2002) THz do not subject a biological tissue to harmful radiation and may provide both imaging and spectroscopic information on biological materials. Needs of: High S/N ratio High acquisition rate and resolution THz database for biological tissues High power to increase sensing and penetration Near-field imaging to increase spatial resolution (up to now 10 microns resolution has been obtained)

  19. Portable detector housing LN2 portable cryostats Far-infrared detector Real-time response to Far-infrared Beams (l > 60 mm) 20 cm Detector layout High TC Superconducting YBa2Cu3O7-x film patterned by photolithography and Heavy-Ion Lithography QCL test source detector housing IEEE Sensors 10 (2010) 863 Physica C 470 (2010) 918 Superconductor Science and Technology 23 (2010) 125008

  20. II. DEVELOPMENT OF • TERAHERTZ CAMERAS • Detectors for the 0.5-5 THz range: • Fast response time (microsecond) for multiplexing readout • Monolithic, Fabricated with industrial processes THz FOCAL PLANE ARRAY BEAM CONDENSER TARGET • Array prototype fabrication at CNR-IFN in Rome • Nanofabrication facility: • Clean room • Electron beam lithography • Thin film deposition • Deep etching BEAM EXPANDER THz POINT-LIKE SOURCE IFN-CNR M. Ortolani, R. Leoni, V. Foglietti, S. Cibella, A. Di Gaspare, E. Giovine, G. Torrioli, F. Evangelisti La Sapienza P. Calvani, S. Lupi, A. Nucara ENEAFrascati A. Doria, G.P. Gallerano, E. Giovenale, A. Petralia, I. Spassovsky, G. Messina SELEX S.I. S.p.A. A. Cetronio, M. Peroni, C. Lanzieri (Finmeccanica group) ERAes s.r.l. B. Mencagli, G. Scrascia, M. Grego

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