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- ItemImaging of carrier-envelope phase effects in above-threshold ionization with intense few-cycle laser fields(College Park, MD : Institute of Physics Publishing, 2008) Kling, M.F.; Rauschenberger, J.; Verhoef, A.J.; Hasović, E.; Uphues, T.; Milošević, D.B.; Muller, H.G.; Vrakking, M.J.J.Sub-femtosecond control of the electron emission in above-threshold ionization of the rare gases Ar, Xe and Kr in intense few-cycle laser fields is reported with full angular resolution. Experimental data that were obtained with the velocity-map imaging technique are compared to simulations using the strong-field approximation (SFA) and full time-dependent Schrödinger equation (TDSE) calculations. We find a pronounced asymmetry in both the energy and angular distributions of the electron emission that critically depends on the carrier-envelope phase (CEP) of the laser field. The potential use of imaging techniques as a tool for single-shot detection of the CEP is discussed. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
- ItemAttosecond electron thermalization in laser-induced nonsequential multiple ionization: Hard versus glancing collisions(College Park, MD : Institute of Physics Publishing, 2008) Liu, X.; De Morisson Faria, C.F.; Becker, W.A recollision-based largely classical statistical model of laser-induced nonsequential multiple (N-fold) ionization of atoms is further explored. Upon its return to the ionic core, the first-ionized electron interacts with the other N - 1 bound electrons either through a contact or a Coulomb interaction. The returning electron may leave either immediately after this interaction or join the other electrons to form a thermalized complex which leaves the ion after the delay Δt, which is the sum of a thermalization time and a possible additional dwell time. Good agreement with the available triple and quadruple ionization data in neon and argon is obtained with the contact scenario and delays of Δt = 0.17 T and 0.265 T, respectively, with T the laser period. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
- ItemTowards time resolved core level photoelectron spectroscopy with femtosecond x-ray free-electron lasers(College Park, MD : Institute of Physics Publishing, 2008) Pietzsch, A.; Föhlisch, A.; Beye, M.; Deppe, M.; Hennies, F.; Nagasono, M.; Suljotil, E.; Wurth, W.; Gahl, C.; Dörich, K.; Melnikov, A.We have performed core level photoelectron spectroscopy on a W(110) single crystal with femtosecond XUV pulses from the free-electron laser at Hamburg (FLASH). We demonstrate experimentally and through theoretical modelling that for a suitable range of photon fluences per pulse, time-resolved photoemission experiments on solid surfaces are possible. Using FLASH pulses in combination with a synchronized optical laser, we have performed femtosecond time-resolved core-level photoelectron spectroscopy and observed sideband formation on the W 4f lines indicating a cross correlation between femtosecond optical and XUV pulses. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
- ItemInterference in strong-field ionization of a two-centre atomic system(College Park, MD : Institute of Physics Publishing, 2008) Ansari, Z.; Böttcher, M.; Manschwetus, B.; Rottke, H.; Sandner, W.; Verhoef, A.; Lezius, M.; Paulus, G.G.; Saenz, A.; Milošević, D.B.Strong-field photoionization of argon dimers by a few-cycle laser pulse is investigated using electron-ion coincidence momentum spectroscopy. The momentum distribution of the photoelectrons exhibits interference due to the emission from the two atomic argon centres, in analogy with a Young's doubleslit experiment. However, a simulation of the dimer photoelectron momentum spectrum based on the atomic spectrum supplemented with a theoretically derived interference term leads to distinct deviations from the experimental result. The deviations may have their origin in a complex electron dynamics during strong-field ionization of the Ar2 dimer. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
- ItemUltrafast optical excitations of metallic nanostructures: From light confinement to a novel electron source(College Park, MD : Institute of Physics Publishing, 2007) Ropers, C.; Elsaesser, T.; Cerullo, G.; Zavelani-Rossi, M.; Lienau, C.Combining ultrafast coherent spectroscopy with nano-optical microscopy techniques offers a wealth of new possibilities for exploring the structure and function of nanostructures. In this paper, we describe newly developed nano-optical methods based on short-pulse laser sources with durations in the 10 fs regime. These techniques are used to unravel some of the intricate dynamics of elementary excitations in metallic nanostructures. Specifically, we explore light localization and storage in plasmonic crystals, demonstrate field enhancement and second harmonic generation from metallic nanotips and describe a novel nanometre-sized source of electron pulses. The rapid progress in this area offers exciting new prospects for probing and controlling electron dynamics in metallic nanostructures with femtosecond temporal and nanometre spatial resolution. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
- ItemSchlussbericht vom 10.08.2004 zum Thema: Verbundprojekt: Aufbau und Test eines Messstandes zur Untersuchung gespeicherter Nanopartikel mit Synchrotronstrahlung : bmb+f-Förderschwerpunkt Kondensierte Materie, Großgeräte der physikalischen Grundlagenforschung(Hannover : Technische Informationsbibliothek (TIB), 2004) Widdra, Wolf[no abstract available]
- ItemAn ultrashort X-ray emission from gas clusters irradiated by ultrashort laser pulses : final report for the project FST-D-ISR-10 ; [Forscherverbund: German Israeli Cooperation in Ultrafast Laser Technologies (GILCULT)](Hannover : Technische Informationsbibliothek (TIB), 2004) MBI[no abstract available]
- ItemMikrooptische Dünnschicht-Komponenten zur Effizienzverbesserung der Kollimation von Diodenlaser-Arrays (MDK)(Berlin : Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, 2002) Nerreter, S.; Seewald, G.; Fischer, A.; Neumann, U.; Tischer, M.; Grunwald, R.[no abstract available]
- ItemPlasma induced pulse breaking in filamentary self-compression(Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2009) Brée, Carsten; Demircan, Ayhan; Skupin, Stefan; Berg´e, Luc; Steinmeyer, GünterA plasma induced temporal break-up in filamentary propagation has recently been identified as one of the key events in the temporal self-compression of femtosecond laser pulses. An analysis of the Nonlinear Schrödinger Equation coupled to a noninstantaneous plasma response yields a set of stationary states. This analysis clearly indicates that the emergence of double-hump, characteristically asymmetric temporal on-axis intensity profiles in regimes where plasma defocusing saturates the optical collapse caused by Kerr self-focusing is an inherent property of the underlying dynamical model.
- ItemErforschung eines diodengepumpten Hochleistungsfaserlasers im cw Betrieb : Fernfeldverteilung eines Multicore Faserlasers mit Talbot Resonator ; Abschlussbericht(Berlin : Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, 2001) Glas, P.[no abstract available]