Library

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
    Absolute magnetometry at nanometer transverse spatial resolution: Holography of thin cobalt films in a scanning transmission electron microscope (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 7418-7424 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A method for the absolute measurement of magnetization at nanometer spatial resolution in magnetic thin films has been developed. A biprism placed in the illumination system of a scanning transmission electron microscope allows the operation of two distinct holography modes. The absolute mode displays a linear change in phase difference for regions of constant magnetization and thickness and the slope determines the magnitude of magnetization. The differential mode displays a constant value of phase difference in these regions allowing a simple and straightforward determination of domain wall profiles. Micromagnetic structure extracted from identical areas of thin Co films is compared using the new holography modes, differential phase constrast Lorentz microscopy and conventional Fresnel Lorentz microscopy in the same instrument.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356658
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Microanalysis on the (200) diffraction intensity to determine the Al concentrations for AlGaAs-GaAs multiple-quantum-well structures (1990)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 67 (1990), S. 698-704 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: By using a nanoprobe electron beam 4 A(ring) in diameter, the [001] nanodiffraction patterns of AlGaAs-GaAs multiple-quantum-well structures have been formed and the epitaxial relationship between AlGaAs and GaAs is confirmed. The intensities of the (200) diffraction disk, monitored by a spot detector, are displayed in two ways: (1) the (200) dark-field scanning transmission electron microscopy (STEM), which shows the layers of AlGaAs and GaAs in contrast, and (2) the (200) line-scan profile, which reveals the (200) intensity distribution of a specimen region of uniform thickness. The thickness and the absolute Al concentration of AlGaAs layers are, respectively, determined from the contrast of, and the (200) thickness contour position in, the (200) dark-field STEM images. The microanalysis on the (200) line-scan profile is used to find the local Al concentrations in AlGaAs layers and to study the interface boundary between the layers of AlGaAs and GaAs. Diffusion of the Al atoms from the AlGaAs layer into the GaAs layer is also reported.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.345774
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Comment on "Electron holographic study of ferroelectric domain walls'' (1993)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 62 (1993), S. 2446-2447 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.109340
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Thickness dependence of ferroelectric domains in thin crystalline films (1994)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 65 (1994), S. 1906-1908 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The thickness dependence of ferroelectric domains in thin free-standing BaTiO3 crystalline films has been studied by transmission electron microscopy. It is found that the widths of ferroelectric domains decrease as the film thickness decreases. This phenomenon may indicate that the ferroelectric properties of thin films are weakened due to surface relaxation effects, including lattice relaxation and a change of spontaneous polarization and charge compensation. The weakening of ferroelectric domains is suggested as a transition state from ferroelectric to paraelectric phase of the BaTiO3 thin film. The thickness of the surface relaxation layer of totally nonferroelectric film is on the order of 10 nm. © 1994 American Institue of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.112835
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Diffuse scattering in electron diffraction patterns. II. Short-range order scattering (1968)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 24 (1968), S. 329-336 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The general method of computing the intensities of diffuse scattering in electron diffraction patterns, outlined by Cowley & Pogany in Part I, has been applied to the case of diffuse scattering given by the short-range ordering in binary solid solutions. If the diffuse scattering from individual crystal slices, of thickness greater than the effective range of ordering, can be assumed to be kinematical, the total diffuse scattering can be expressed in terms of the usual short-range order parameters, αi, and `dynamical factors'. When the diffuse scattering from a slice cannot be assumed to be kinematical, as in the case of copper–gold alloys, a new type of order parameter, involving some higher-order correlations, must be introduced. Expressions are derived for the absorption coefficients which must be applied to the Bragg reflections. The intensity of diffuse scattering from a single slice of crystal is calculated for a simple domain model of short-range order to evaluate the order of magnitude of departures from kinematical scattering and the possible sensitivity of the diffuse intensity to higher-order correlations. The methods are outlined by which diffuse intensity could be calculated for the whole crystal by a modification of the n-beam dynamical multi-slice procedure and a procedure for the approximate calculation of multiple-diffuse scattering is suggested.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739468000653
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    The determination of structure factors from dynamical effects in electron diffraction (1969)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 25 (1969), S. 129-134 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: In order to obtain accurate data on structure factors from electron diffraction data, it is necessary to take into account the inevitable n-beam dynamical diffraction effects. The comparison of intensity values from detailed computer calculations with observed intensities from perfect crystals is reviewed for the cases of convergent beam diffraction patterns from MgO crystals of uniform thickness and of dark-field images of wedge-shaped crystals of silicon. An analysis of the sources of error in each case suggests that it may be possible to derive structure factor values with an accuracy of better than one per cent. The method, recently proposed by Watanabe et al. [Acta Cryst. (1968). A24, 249] for deriving structure factors from the values of accelerating voltages for which some Kikuchi lines disappear, is reviewed and possible sources of error are examined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739469000209
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Diffuse scattering in electron diffraction patterns. I. General theory and computational methods (1968)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 24 (1968), S. 109-116 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The solution of the n-beam dynamical theory of the diffraction of electrons by crystals is generalized to cover the case of diffraction by crystals containing defects and disorders, including thermal motion. The conditions and assumptions under which practical computer calculations of diffuse intensities can be made are explored on the basis of the slice approach of Goodman and Moodie, although matrix methods are equally applicable. It is shown that, if the range of correlation of the deviations from the perfect crystal lattice is small, the total diffuse scattering can be expressed in terms of dynamical factors which multiply the intensities calculated using the kinematical approximation. Simple expressions are derived for the absorption coefficients which must be applied to the sharp Bragg reflexions to take account of the energy lost from them into the diffuse scattering. The possibility that the intensity of diffuse scattering may show dependence on the range of correlation of the defects is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739468000148
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Kinematical diffraction from solid solutions with short-range order and size effect (1968)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 24 (1968), S. 557-563 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: A new approach to the kinematical theory has been developed for the case of binary alloy solid solutions with short-range ordering of the atoms and displacements of the atoms from the average lattice sites due to departures of the effective atomic radii from the average for the alloy. Both the pseudo-temperature factor on the Bragg reflexions and the diffuse scattering intensity are shown to depend on summations over higher-order correlation parameters, defined in terms of the probabilities that groups of three, four or more sites should be occupied in specific ways. Expressions involving these parameters, and the usual short-range order parameters, αi, are derived with terms of up to the second order in the displacement parameters for the Huang scattering around the fundamental Bragg reflexions, for the short-range order diffuse peaks, and for additional diffuse scattering depending on higher-order correlation parameters only. Special cases of practical significance are explored, and some estimates are made of the relative magnitudes of the terms not included in previous treatments of this problem.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S056773946800118X
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Theoretical and experimental studies of electron resonance effects in reflection high-energy electron diffraction (1991)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 47 (1991), S. 317-327 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The electron resonance effect for 100 keV electrons incident on the surface of GaAs (110) in RHEED is studied by theoretical simulations using multislice theory and experimental observations. The exact resonance conditions, effective resonance region, effective penetration depth of electrons at or near the resonance condition and scattering processes involved for the resonance effect are investigated. It is found that the intensity of the 440 specularly reflected beam is mainly due to direct reflection from the surface atomic layer and beam enhancement due to surface channeling effects under the resonance conditions seems to be insignificant. For the 880 specularly reflected beam most of the electron intensity penetrates the surface and is diffracted by the crystal. The resonance condition for the 880 specular beam is satisfied when the transmitted beam excites a strong surface wave which propagates in the direction parallel or nearly parallel to the surface and is localized in the surface region by the surface potential barrier; double diffraction from the surface beam to the specular beam then enhances the total intensity in the specular beam. The exact resonance condition for the 880 beam is found to be at the glancing angle of 35.7 mrad and the azimuth angle of 29.7 mrad. A strong wave field is localized in the surface region at the resonance condition with an effective electron penetration depth of ̃5 Å, which increases to ̃35 Å on going to the nonresonance conditions. The effective resonance region for the 880 spot is ̃2 mrad about the azimuth angle and 1̃ mrad about the glancing angle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S010876739001025X
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Irradiation effects in beryllia and zinc oxide (1966)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 21 (1966), S. 192-196 
    Details
    ISSN: 0001-5520
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0365110X66002603
    Library Location Call Number Volume/Issue/Year 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...