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
    Temperature dependence of electron transmission through organized organic thin films (2000)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 113 (2000), S. 7571-7577 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The temperature dependence of electron transmission through various organized organic thin films (OOTFs) was investigated. For most systems a strong dependence of the transmission efficiency on temperature was observed, even for a relatively small temperature range. The well defined structure of the OOTFs and the monitoring of the angular dependence of both the initial and the final velocities of photoelectrons were used to reveal the mechanism behind the temperature effect and further elucidate the transmission mechanism. A simple model, which assumes that the electron transmission yield is much higher along the organic chains than in any other direction, was able to reproduce the experimental observations. We find that the photoelectron transmission yield through OOTFs is extremely sensitive to the structural order in the film. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1313238
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Magnetic properties of exchange-coupled Fe/FeO bilayers : The 40th annual conference on magnetism and magnetic materials (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 5106-5108 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetic, structural and microstructural properties of sputtered Fe thin films and Fe(backward-slash)Fe–O bilayers were studied as a function of the Fe layer thickness, the type of the Fe oxide and the substrate used. Two different ways to prepare the oxide layers were used; postdeposition oxidation and reactive sputtering. Postdeposition oxidation produced films with mixed Fe–oxides (FeO, Fe3O4, Fe2O3); however reactive sputtering led to bilayers with controlled stoichiometry, Fe(backward-slash)FeO, Fe(backward-slash)Fe3O4, and Fe(backward-slash)FE2O3, respectively. The coercivity of both the Fe films and fE(backward-slash)Fe–O bilayers, deposited on substrates with or without Cr buffer layer, was found to increase with decreasing Fe film thickness. The coercivity of the samples deposited on a Ag buffer layer was much lower and did not change substantially with the Fe film thickness. The presence of the Fe–oxide layer led to a large increase of coercivity. This is attributed to the higher anisotropy of the oxide and to exchange coupling of Fe–oxide with the softer Fe layer. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.361316
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Optical constants of epitaxial AlGaN films and their temperature dependence (1997)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 82 (1997), S. 5090-5096 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have studied the dependence of the absorption edge and the refractive index of wurtzite AlxGa1−xN films on temperature and composition using transmission and photothermal deflection spectroscopy. The Al molar fraction of the AlxGa1−xN films grown by plasma induced molecular beam epitaxy was varied through the entire range of composition (0≤x≤1). We determined the absorption edges of AlxGa1−xN films and a bowing parameter of 1.3±0.2 eV. The refractive index in the photon energy range between 1 and 5.5 eV and temperatures between 7 and 295 K was deduced from the interference fringes. The static refractive index n(0) changed from 2.29 for GaN to 1.96 for AlN at room temperature. A variation of temperature from 295 to 7 K resulted in a decrease of refractive index (at photon energies close to the band gap) by 0.05±0.01 and in an energy shift of the absorption edge of about 64±5 meV independent of the Al content of the films. Using the Kramers–Kronig dispersion relation and an approximation for the dispersion coefficient for photon energies near the band gap, the refractive index could be described as a function of photon energy, Al content, and temperature. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.366309
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Electronic oxide polarizability and optical basicity of simple oxides. I (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 1736-1740 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The average electronic oxide polarizability α02− of numerous single component oxides has been calculated on the basis of two different properties: linear refractive index n0 and energy gap Eg, which have demonstrated remarkable correlation. The optical basicity Λ of the oxides has been estimated on the basis of average electronic oxide polarizability calculated from the refractive index Λ(n0) and the energy gap Λ(Eg). A good agreement has been observed between the optical basicity data obtained using independent initial quantities. The simple oxides have been separated into three groups according to the values of their oxide polarizability. The α02− values (above 3 A(ring)) obtained for PbO, Sb2O3, and Bi2O3 have been attributed to the high cation polarizability and the presence of a lone pair in the valence shell of the cation. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.360962
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Linear and nonlinear optical properties of simple oxides. II (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 1741-1745 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A suitable relationship between the linear refractive index n0, the energy gap Eg, and the nonlinear refractive index n2 has been looked for on the basis of experimental and theoretical data reported in the literature for numerous simple oxides. It has been established that the nonlinear refractive index increases with increasing linear refractive index and decreasing energy gap of the oxides. This is related to the increasing metallicity of the oxides. Oxides with a high nonlinear refractive index posses a metallization criterion of approximately 0.30–0.45. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.360963
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Magnetoresistance in (Fe–Co)/Ag films : The 6th joint magnetism and magnetic materials (MMM)−intermag conferenc (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 6799-6801 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The structural and magnetotransport properties of (FeyCo1−y)100−xAgx films were studied as a function of composition. Giant magnetoresistance (GMR) values were measured in these granular films, with the best GMR obtained for the composition (Fe0.33Co0.67)27Ag73, with values of 29% at 30 K and 11.7% at 300 K. XRD and TEM results have shown a fcc crystal structure with a relatively homogeneous microstructure. Magnetic data for the samples with the best GMR indicate a superparamagnetic behavior. The narrow peak in thermomagnetic data and low blocking temperature suggest a small and uniform size distribution of magnetic granules. A summary of the electrical transport properties is presented, in relation to the structural, microstructural, and magnetic properties.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.358134
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Thermal-wave study of the microstructure of lead titanate zirconate and PbTiO3-based ceramics (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 71 (1992), S. 4887-4891 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The microstructure of lead titanate zirconate and PbTiO3-based ceramics is investigated with thermal waves. The photoacoustic data obtained by a gas-microphone method show the presence of thermal-wave diffraction within the samples. The comparison with scanning electron micrographs allows the influence of the grain size and the volume of the glassy phase on the photoacoustic signal to be determined. The influence of the thermal parameters is also discussed. Analysis of the photoacoustic behavior of the investigated ceramic samples is made using the Opsal–Rosencwaig theory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.350634
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Ion source with rf autogenerating beam-plasma discharge : Proceecings of the fourth International Conference on Ion Sources (1992)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 63 (1992), S. 2575-2577 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: An ion source was developed to meet such contradictory requirements as a high-perveance at a low-beam energy, ion selection, and a possibility to produce metal and multicharged ions. An electron beam in a magnetic field is used to produce and heat plasma in a discharge chamber to form an ion emitter. The particular feature of the source is generation of rather powerful rf auto-oscillations in the contour coupled with a special electrode system, the first harmonic being tuned in a wide frequency range up to 100 MHz. Provided rf power is used for an auxiliary plasma heating in a discharge chamber with a magnetic nozzle configuration, an additional longitudinal ion acceleration to the emissive electrode and a significant (by a factor of 2–3) increase of an ion yield at a lowered gas pressure are observed. When rf power is loaded onto a resonance structure installed behind an emissive electrode, an ion selective acceleration takes place.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1142894
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Microstructure and high temperature magnetic properties of Sm(Co, Cu, Fe, Zr)z (z=6.7–9.1) permanent magnets (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 85 (1999), S. 2800-2804 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effect of ratio z on the high temperature magnetic properties of Sm(Co, Fe, Cu, Zr)z magnets have been examined in a range of ratio z values from 6.7 to 9.1. Reasonably high coercivity at room temperature has been achieved in all the magnets. It was found that the lower the ratio z, the smaller the temperature coefficient of coercivity. When the ratio z=7.0, a temperature coefficient of coercivity of −0.03%/°C can be achieved, which is more than eight times smaller than the magnet with z=8.5. A coercivity of more than 10 kOe has been obtained at 773 K for the newly developed magnets, which is believed to be the highest coercivity at 773 K ever reported. Transmission electron microscope studies showed that the cell size decreases with the decrease of the ratio z, while the density of lamella phase remains almost the same. This suggests that smaller cell size leads to a smaller temperature coefficient of intrinsic coercivity. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.369597
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Memory effect and temperature behavior in spin valves with and without antiferromagnetic subsystems (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 86 (1999), S. 5692-5695 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Temperature behavior and memory effect in standard spin valves (SV) and SVs with synthetic antiferromagnetic (Co/Ru/Co) (SV-SAF) subsystems have been studied. SV-SAFs show much better temperature stability. Memory effect refers to the phenomenon that the exchange bias can be altered at temperatures (TR's) much lower than the blocking temperature (TB), and these temperatures (TR's) are imprinted into SVs. The memory effect greatly deteriorates the magnetoresistance behaviors in SV. Our results suggest that the memory effect is caused by a distribution of local blocking temperatures (Tb's). The magnetization state in the pinned layer is critical in determining the temperature behavior of HE and magnetoresistance. By partially reversing the magnetization in the pinned ferromagnetic (FM) layers, we are able to separate the temperature dependencies of the local exchange bias (He) associated with regions consisting of different Tb's. Two features have been observed: (1) the local exchange bias (He) with a narrow Tb distribution has a weak temperature dependence; (2) the simple algebraic sum of local He's nearly reproduce the total HE with the difference between these two quantities representing the domain wall energy in the FM layer. On the other hand, SV-SAFs show strong resistance to memory effects because of two factors; the strong exchange coupling through the Ru layer, and the net magnetic moment of Co/Ru/Co layers in SV-SAF being close to zero. The former makes the two SV-SAF FM layers behave coherently, while the latter makes the interaction between the SV-SAF and the external field negligibly small. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.371580
    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...