Sökning: "EMCD"

Hittade 5 uppsatser innehållade ordet EMCD.

  1. 1. Reducing the dynamical diffraction effects in EMCD by electron beam precession

    Kandidat-uppsats,

    Författare :Arvid Forsberg; [2020]
    Nyckelord :electron microscope; TEM; transmission electron microscope; EMCD; electron energy-loss magnetic chiral dichroism; magnetism; precession electron diffraction; crystals; crystallography;

    Sammanfattning : Dynamical effects are known to reduce the signal to noise ratio in EMCD measurements making them highly dependent on sample thickness. Precession of the electron beam has been shown to reduce these effects in ordinary crystallography. LÄS MER

  3. 2. Influence of non-dipole transitions on the extraction of EMCD

    Master-uppsats, Uppsala universitet/Materialteori

    Författare :Paul Michel Zeiger; [2019]
    Nyckelord :;

    Sammanfattning : ELNES-spectra of the L3 and L2-edge of bcc-iron are simulated using a Bloch wave method for the calculation of the DDSCS within a 1st-order Born approximation of the inelastic electron scattering process in order to study the influence of non-dipole terms on the EMCD-signal. The necessary electronic structure information is obtained from a DFT-calculation using WIEN2k. LÄS MER

  4. 3. Simulation of High-Angle Annular Dark Field Images of Crystals

    L3-uppsats, Uppsala universitet/Materialteori

    Författare :Paul Michel Zeiger; [2017]
    Nyckelord :TEM HAADF Molecular Dynamics EMCD Vortex Beams;

    Sammanfattning : Multislice HAADF - STEM image simulations of SrTiO 3 are performed at 300 K.The procedure of these simulations and the used techniques are briefly ex-plained and reasoned. The results are presented and discussed in a conciseway and in an attached paper a comparison to experimental images is made. LÄS MER

  5. 4. Programming a TEM for magnetic measurements : DMscript code for acquiring EMCD data in a single scan with a q-E STEM setup

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Tillämpad materialvetenskap

    Författare :Linus Schönström; [2016]
    Nyckelord :EMCD; magnetic dichroism; q-E STEM; DMscript; DigitalMicrograph scripting; custom STEM acquisition; SI hookup system; Spectrum Imaging hookups;

    Sammanfattning : Code written in the DigitalMicrograph® scripting language enables a new experimental design for acquiring the magnetic dichroism in EELS. Called the q-E STEM setup, it provides simultaneous acquisition of the dichroic pairs of spectra (eliminating major error sources) while preserving the real-space resolution of STEM. LÄS MER

  7. 5. Shape functions in calculations of differential scattering cross-sections

    Kandidat-uppsats, Institutionen för fysik och astronomi

    Författare :Anders Johansson; [2010]
    Nyckelord :Differential cross-sections; DDSCS; EELS; ELNES; EMCD; Dynamical diffraction theory; thickness function; shape function; shape amplitude;

    Sammanfattning : Two new methods for calculating the double differential scattering cross-section (DDSCS) in electron energy loss spectroscopy (EELS) have been developed, allowing for simulations of sample geometries which have been unavailable to earlier methods of calculation. The new methods concerns the calculations of the thickness function of the DDSCS. LÄS MER