ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Evidence of magnetic fields imprinted in ferromagnetic targets by the spontaneous magnetic field of a laser-produced plasma demonstrated by after-pulse pulsations of Kα emission (1997)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 4 (1997), S. 3676-3683 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The observation of an unusually long sequence of Kα pulses from planar Fe foil targets irradiated by a 180 ps laser pulse at intensities of(0.1–3)×1016 W/cm2 is presented. The duration of the Kα emission was up to 5 ns: approximately 30 times longer than the laser pulse. A proposed interpretation of these observations is that suprathermal electrons generated in the laser-produced plasma survive after the laser pulse and are gradually decelerated as they circulate in the magnetic field imprinted during the laser pulse in the ferromagnetic target material. Short bursts of Kαemission occur as these electrons pass through the target. The magnetic field in the cold part of the ferromagnetic target with temperature below the Curie temperature is an integral imprint of the spontaneous magnetic field generated in the laser-produced plasma. A model of this process provides a good fit to the experimental data. The effect could be useful as a diagnostic tool for measuring the spontaneous magnetic field and the energy of fast electrons. These results also open an opportunity for studies of magnetization processes in a ferromagnetic at an extremely high magnetic field: on the megagauss scale. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.872565
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Ultrafast ablation with high-pulse-rate lasers. Part II: Experiments on laser deposition of amorphous carbon films (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 85 (1999), S. 4222-4230 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Ultrafast pulsed laser deposition is a novel technique for depositing particle-free, thin solid films using very high repetition rate lasers. The process involves evaporation of the target by low energy laser pulses focused to an optimum intensity to eliminate particles from the vapor. This results in films with very high surface quality while the very high repetition rate increases the overall deposition rate. Here we report an experimental demonstration of the process by creating ultrasmooth, thin, amorphous carbon films using high repetition rate Nd:YAG lasers. Both a 10 kHz, 120 ns Q-switched Nd:YAG laser, or a 76 MHz 60 ps mode-locked Nd:YAG laser were used in the experiments. The number of particles visible with an optical microscope on the carbon film deposited using the mode-locked laser was less than one particle per mm2. Scanning electron microscopy images demonstrated that the deposited film had a very fine surface texture with nanoscale irregularities. Atomic force microscopy surface microroughness measurements revealed a saturation-like behavior of the root-mean-square roughness at 〈12 nm over the whole deposited surface area for 10 kHz Q-switched laser evaporation; and almost at the atomic level (〈1 nm) for the 76 MHz mode-locked laser evaporation. Raman spectroscopy of the deposited films indicated that they consisted of a mixture of sp3 and sp2 bonded amorphous carbon. The thickness of the amorphous carbon film deposited simultaneously on two 4 in. silicon wafers varied by only ±5% over an area of ∼250 cm2. The deposition rate was ∼2–6 Å/s at a distance of ∼150 mm from the target, which is 10 to 25 times higher than that achieved with conventional high energy low repetition rate nanosecond lasers. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.370334
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    GaAs based anti-resonant Fabry–Perot saturable absorber fabricated by metal organic vapor phase epitaxy and ion implantation (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 70 (1997), S. 3428-3430 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have fabricated an antiresonant Fabry–Perot saturable absorber (A-FPSA), for potential use in laser passive mode locking, using metalorganic vapor phase epitaxy followed by ion implantation and thermal annealing. We show that the implantation/annealing cycle shortens the free-carrier dwell time without degrading the other optical properties of the A-FPSA. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.119192
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Nonlinear optical absorption and temporal response of arsenic- and oxygen-implanted GaAs (1999)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 74 (1999), S. 1993-1995 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have measured the nonlinear optical absorption of arsenic and oxygen implanted epitaxial GaAs for a range of ion doses and annealing temperatures. The response time, τA, and a parameter, Mmax, which characterizes the performance of the structures as modulators, are both reduced by implantation, and correspondingly the nonbleachable losses are increased. We show that similar combinations of (τA, Mmax) can be achieved using either ion species and various combinations of dose and annealing temperatures. Furthermore, the data were all located on a well-defined curve in the (τA, Mmax) plane, provided amorphization, which occurs at high implant doses, was avoided. We deduce that there exists a limit to the modulation if a specific response time is required. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.123724
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    The electron affinity of iridium (1997)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 106 (1997), S. 5783-5784 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The electron affinity of iridium has been measured to be 12 613(4) cm−1. A pulsed dye laser beam perpendicular to an ion beam photodetached the negative iridium ions, and the relative cross section near threshold was measured by detecting the fast neutrals. The threshold was determined by fitting the cross section to the Wigner law. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.473602
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Coset Decomposition of Space Groups: Applications to Domain Structure Analysis (1997)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 53 (1997), S. 456-466 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Left- and double-coset decompositions of space groups are systematically analysed by putting the emphasis on the introduction of special auxiliary groups. An algorithm is tailored to exploit the specific structure of space groups. The new results are, amongst others, an efficient alternative method to determine for space groups minimal sets of double-coset representatives and a general formula that gives the structure and number of left cosets that are contained in double cosets. Left-coset and double-coset decompositions of space groups are exploited in domain structure analysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0108767397003450
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Interaction of two-dimensional spatial incoherent solitons in photorefractive medium (1999)
    Springer
    Applied physics 68 (1999), S. 975-982 
    Details
    ISSN: 1432-0649
    Keywords: PACS: 42.65.Tg; 03.40.Kf; 42.65.Hw
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. We present a review of our recent theoretical and experimental results on the interaction of incoherent two-dimensional solitary beams in PR SBN crystals. We show that the inherent anisotropy of PR nonlinearity strongly affects the interaction between solitons. Theoretical and experimental results reveal that solitons interacting in a plane perpendicular to the direction of external biasing field always attract, whereas those colliding in a plane of the field exhibit anomalous behaviour. They may experience both attractive and repulsive forces, depending on their mutual separation. We also show that this anisotropy results in the complicated topology of soliton trajectories, featuring periodic collisions, prolonged mutual spiraling and collapse, depending on the initial conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003400050733
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A CAD-based visual simulator for designing flexible automated material handling and transportation systems (1998)
    Springer
    The international journal of advanced manufacturing technology 14 (1998), S. 555-562 
    Details
    ISSN: 1433-3015
    Keywords: CAD ; Flexible manufacturing ; Material handling ; Simulation ; Visualisation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract A software system is presented for simulating the behaviour of an automated material handling and transportation system typically used in flexible manufacturing. The program is written in the UPL language on top of a commercially available CAD system. It makes use of a discrete event simulation model written in ECSL to generate a schedule of events defining an animation scenario. The program relies on a graphical library of modular component elements that enable structured automated material handling and transportation system elements to be created. The motion patterns are generic and are implemented as procedures that can be associated with any entity as required. Motion employs the concept of entity associativity within the CAD environment in order to apply the same motion patterns to groups of entities. The latter retain, however, their individual motion specification. Advantages of the program include inherent integration with CAM, availability of a host of parent CAD facilities and thus ability to visualise facility performance and to appraise design in detail.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01301699
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Laser ablation of carbon at the threshold of plasma formation (1999)
    Springer
    Applied physics 69 (1999), S. S121 
    Details
    ISSN: 1432-0630
    Keywords: PACS: 52.50.Jm; 79.20.Ds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract. The ionization of laser-ablated vapours with lasers producing ns duration pulses at various wavelengths has been studied in order to understand the mechanisms of the vapour–plasma transition. It has been established that there are several regimes characterizing the laser–target interaction which depend on laser intensity, wavelength, and pulse duration. The range of laser intensities for optimal laser evaporation is determined by the condition of transparent vapours. The intensity range is upper-limited by the opaque plasma formation due to vapour optical breakdown. Results are given for laser evaporation of graphite with Nd:YAG laser (1.064 μm), KrF laser (248 nm) and ArF laser (193 nm). For the UV laser wavelength the regime of skin-effect interaction was proposed as the mechanism of ion acceleration, and the range of validity of the skin-effect mode was established. With UV lasers the interaction has a bimodal nature: the interaction may proceed initially in the skin effect regime, resulting in a few high-energy ions, until hydrodynamic expansion begins at a later stage. The skin-effect interaction at the initial stage of the UV laser pulse gives the first, to our knowledge, explanation for the acceleration of ions up to ∼100 eV at low laser intensities of 108–109 W/cm2 and ns-range pulse duration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003399900387
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    HEAVY METAL CONTAMINATED SOILS IN AN OLD INDUSTRIAL AREA OF WALES, GREAT BRITAIN: SOURCE IDENTIFICATION THROUGH STATISTICAL DATA INTERPRETATION (1997)
    Springer
    Water, air & soil pollution 94 (1997), S. 85-98 
    Details
    ISSN: 1573-2932
    Keywords: soil ; pollution ; heavy metals ; smelters ; factoranalysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract A combined statistical and computergraphic approach is proposed for apportionment and attribution of soil contaminants in complex areas. The field test site lies north of Swansea, south Wales and contains two major pollutant sources, an active nickel refiner and (4 km away) the site of major base metal smelting in the nineteenth century (the Lower Swansea Valley reclamation study area). Soil samples (70 samples, 0–15 cm) were collected on a regular grid of 1000 m interval. They were extracted using 0.05 M diammonium EDTA and the extracts analysed for Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn. Soil pH and %organic content were also determined. Factor analysis yielded three groups which explained 73.8% of the data variance (1: Cd, Cu, %OM, Pb, Zn, Ni; 2: Cd, Zn, Mn, pH; 3: Cu, Mn, Co, Ni, Fe). Isoline plots were classifiable into the same three groups. It was concluded that factor 3 contained those elements associated with smelter emissions, factor 1 with contamination from the Lower Swansea Valley and in factor 2 pedogenetic processes control the occurrence of the elements.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1026478427782
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...