Processing and analysis of X-ray photoelectron diffraction data using IGOR Pro

Abstract

A software package is presented for nearly real‐time display of diffractograms during X‐ray photoelectron diffraction (XPD) data acquisition and for processing and analysis after an experiment. During the experiment, the package is able to automatically read X‐ray photoelectron spectroscopy (XPS) data, perform initial data processing and project intensity values as XPD diffractograms. Four display modes are supported. After the experiment, the package is able to open, process and analyze XPD patterns. The processing functions include rotation, cropping, creating a full 2π pattern using symmetry operations, smoothing and converting a pattern to an image suitable for publication. The analysis functions include displaying polar angles, azimuthal angles, intensity, the core level spectrum at a selected angular data point, and azimuthal and radial profiles. The package also integrates fitting functions for core level spectra. The package is developed using the IGOR Pro scripting language. A graphical user interface has been developed to allow all the operations just by mouse clicking. The package is designed to interface directly with an XPD system at the Saclay center of the French Atomic Energy and Alternative Energies Authority, but the algorithms are generally applicable and can be readily adapted to other XPD systems.

Oxide materials as building blocks for artificial topological insulators

“…After an incoming photon is absorbed by an atom (the emitter), a photoelectron wave is moving outwards in a certain direction. Since the neighboring atoms act as scatterers, constructive and destructive interference occurs between the direct and scattered waves [233,234,238,239,252,253]. When the kinetic energy of the emitted photoelectron exceeds a few hunderd electronvolts, the scattering amplitude is mostly focussed in the forward direction leading to one outstanding peak in the interference pattern [234,238,241,242], see upper right corner in Fig.…”