Auger Electron and Photoelectron Diffraction in Magnetic Thin Films

1993 ◽  
Vol 313 ◽  
Author(s):  
Y.U. Idzerda ◽  
D.E. Ramaker
Keyword(s):  
Quantum Number ◽  
Auger Electron ◽  
Spherical Wave ◽  
Magnetic Thin Films ◽  
Single Scattering ◽  
Final State ◽  
Photoelectron Diffraction ◽  
Angular Momentum Quantum Number ◽  
Cluster Calculations

ABSTRACTThe role of the final-state character of the emitted electron in Auger electron diffraction (AED) and x-ray photoelectron diffraction (XPD) is examined with respect to magnetic materials. Single scattering cluster calculations with the inclusion of the spherical wave character and the final-state character of the emitted electron (both angular momentum quantum number and magnetic quantum number) show that selective emission from different M-levels, generated by a non-statistical distribution of initial M-levels or by an M-selective excitation process, results in distinctly different emission patterns.

scholarly journals Circular Dichroism in Cu Resonant Auger Electron Diffraction

2016 ◽  
Vol 230 (4) ◽  
Author(s):  
Fumihiko Matsui ◽  
Naoyuki Maejima ◽  
Hirosuke Matsui ◽  
Hiroaki Nishikawa ◽  
Hiroshi Daimon ◽  
...  
Keyword(s):  
Angular Momentum ◽  
Quantum Number ◽  
Auger Electron ◽  
Polarized Light ◽  
Core Hole ◽  
Initial State ◽  
Final State ◽  
Shift Measurement ◽  
Auger Electrons ◽  
The Core

AbstractUpon a core level excitation by circularly polarized light (CPL), the angular momentum of light, i.e. helicity, is transferred to the emitted photoelectron. This phenomenon can be confirmed by the parallax shift measurement of the forward focusing peak (FFP) direction in a stereograph of the atomic arrangement. The angular momentum of the emitted photoelectron is the sum of CPL helicity and the magnetic quantum number (MQN) of the initial state that define the quantum number of the core hole final state. The core hole may decay via Auger electron emission, where in this two electron process the angular momentum has to be conserved as well. Starting from a given core hole, different Auger decay channels with different final state energies and angular momenta of the emitted Auger electrons may be populated. Here we report the observation and formulation of the angular momentum transfer of light to Auger electrons, instead of photoelectrons. We measured photoelectron and Auger electron intensity angular distributions from Cu(111) and Cu(001) surfaces as a function of photon energy and photoelectron kinetic energy. By combining Auger electron spectroscopy with the FFP shift measurements at absorption threshold, element- and MQN-specific hole states can be generated in the valence band.

DETERMINATION OF THE OVERLAYER/SUBSTRATE REGISTRY IN Ni(1 ML)/Pt(111) BY ANGLE-SCANNED PHOTOELECTRON DIFFRACTION

1995 ◽  
Vol 02 (06) ◽  
pp. 787-793 ◽  
Author(s):  
M. SAMBI ◽  
E. PIN ◽  
G. GRANOZZI
Keyword(s):  
Factor Analysis ◽  
Spherical Wave ◽  
Theoretical Data ◽  
Single Scattering ◽  
Photoelectron Diffraction ◽  
R Factor

The site (fcc or hcp) occupied by the atoms of a Ni ML deposited on Pt (111) is determined in this paper using angle-scanned photoelectron diffraction (PD). A full 2π MgK α-excited Ni-2p 3/2 PD pattern from 1-ML Ni deposited on Pt(111) is compared to single scattering cluster-spherical wave (SSC-SW) simulations and the agreement between experimental and theoretical data is quantified by R-factor analysis. From the present investigation it turns out that Ni atoms occupy hcp sites. In addition, the Ni-Pt distance has been estimated to be 2.5±0.1 Å.

X-RAY PHOTOELECTRON DIFFRACTION STUDY OF A LONG-RANGE-ORDERED ACETATE LAYER ON Ni(110)

2000 ◽  
Vol 07 (01n02) ◽  
pp. 25-36 ◽  
Author(s):  
M. NOWICKI ◽  
A. EMUNDTS ◽  
J. WERNER ◽  
G. PIRUG ◽  
H. P. BONZEL
Keyword(s):  
Room Temperature ◽  
Solid Angle ◽  
Single Scattering ◽  
Real Space ◽  
X Ray ◽  
Photoelectron Diffraction ◽  
Acetate Complex ◽  
Cluster Calculations ◽  
Model Layer ◽  
Good Agreement

An investigation of acetic acid adsorption on Ni(110) at room temperature by LEED and X-ray photoelectron diffraction reveals a well-ordered c(2 × 2) acetate overlayer with a molecular coverage near 0.5. Large solid angle maps of angle-resolved C 1s and O 1s intensities from this layer show intense maxima due to electron forward scattering by nearby atoms, either of the same acetate or of neighboring acetate species. The data provide strong evidence for acetate in a bidentate configuration, bonded through both oxygen atoms to the surface and aligned along the [Formula: see text] surface azimuth. A real space model for the c(2 × 2) acetate layer has been derived and single scattering cluster calculations for this model layer have been carried out for C 1s and O 1s emissions. Allowing for changes in intramolecular bond length of the acetate relative to those in a Ni-acetate complex, good agreement between experimental and theoretical C 1s and O 1s distributions was obtained.

Transmission Electron Microscopy studies of texture of Cr underlayer of magnetic recording hard disk

1991 ◽  
Vol 49 ◽  
pp. 580-581
Author(s):  
L. Tang ◽  
G. Thomas ◽  
M. R. Khan ◽  
S. L. Duan
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Magnetic Recording ◽  
Magnetic Thin Films ◽  
Magnetic Films ◽  
Substrate Bias ◽  
Epitaxial Relationship ◽  
Transmission Electron

Cr thin films are often used as underlayers for Co alloy magnetic thin films, such as Co1, CoNi2, and CoNiCr3, for high density longitudinal magnetic recording. It is belived that the role of the Cr underlayer is to control the growth and texture of the Co alloy magnetic thin films, and, then, to increase the in plane coercivity of the films. Although many epitaxial relationship between the Cr underlayer and the magnetic films, such as ﹛1010﹜Co/ {110﹜Cr4, ﹛2110﹜Co/ ﹛001﹜Cr5, ﹛0002﹜Co/﹛110﹜Cr6, have been suggested and appear to be related to the Cr thickness, the texture of the Cr underlayer itself is still not understood very well. In this study, the texture of a 2000 Å thick Cr underlayer on Nip/Al substrate for thin films of (Co75Ni25)1-xTix dc-sputtered with - 200 V substrate bias is investigated by electron microscopy.

Role of interface alloying in Fe whisker/Cr/Fe(001) structures, angular-resolved Auger electron and MOKE studies

1996 ◽  
Vol 156 (1-3) ◽  
pp. 215-218 ◽  
Author(s):  
B. Heinrich ◽  
J.F. Cochran ◽  
D. Venus ◽  
K. Totland ◽  
C. Schneider ◽  
...  
Keyword(s):  
Auger Electron

scholarly journals Study of Rare Mesonic Decays Involving Di-Neutrinos in Their Final State

2018 ◽  
Vol 2018 ◽  
pp. 1-20
Author(s):  
Azeem Mir ◽  
Farida Tahir ◽  
Shakeel Mahmood ◽  
Shi- Hai Dong
Keyword(s):  
Branching Fractions ◽  
New Physics ◽  
Supersymmetric Model ◽  
Final State ◽  
Yukawa Couplings ◽  
Leptonic Decays ◽  
Pseudoscalar Mesons ◽  
Theoretical Predictions ◽  
Minimal Supersymmetric Model

We have studied phenomenological implication of R-parity violating (Rp) Minimal Supersymmetric Model (MSSM) via analyses of pure leptonic (M→νν¯) and semileptonic decays of pseudoscalar mesons (M→Xνν¯). These analyses involve comparison between theoretical predictions made by Rp MSSM and the Standard Model (SM) with the experimental results like branching fractions (Br) of the said process. We have found, in general, that Rp contribution dominates over the SM contribution, i.e., by a factor of 10 for the pure leptonic decays of KL,S and by 102 and 104 in case of Bs and Bd, respectively. Furthermore, the limits obtained on Rp Yukawa couplings (λαkβ′λαkγ′⁎) by using Br  (M→Xνν¯) are used to calculate Br  (M→νν¯). This demonstrates the role of Rp MSSM as a viable model for the study of new physics contribution in rare decays at places like Super B factories, KOTO (J-PARC) and NA62 at CERN.

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