Practical Aspects of Removing the Effects of Elastic and Thermal Diffuse Scattering from Spectroscopic Data for Single Crystals

Abstract

A method to remove the effects of elastic and thermal diffuse scattering (TDS) of the incident electron probe from electron energy-loss and energy-dispersive X-ray spectroscopy data for atomically resolved spectrum images of single crystals of known thickness is presented. By calculating the distribution of the probe within a specimen of known structure, it is possible to deconvolve the channeling of the probe and TDS from experimental data by reformulating the inelastic cross-section as an inverse problem. In electron energy-loss spectroscopy this allows valid comparisons with first principles fine-structure calculations to be made. In energy-dispersive X-ray spectroscopy, direct compositional analyses such as ζ-factor and Cliff-Lorimer k-factor analysis can be performed without the complications of channeling and TDS. We explore in detail how this method can be incorporated into existing multislice programs, and demonstrate practical considerations in implementing this method using a simulated test specimen. We show the importance of taking into account the scattering of the probe in k-factor analysis in a zone axis orientation. The applicability and limitations of the method are discussed.

Experimental verification of orbital engineering at the atomic scale: Charge transfer and symmetry breaking in nickelate heterostructures

“…The authors acknowledge that with the electron probe in a channeling condition (i.e., a zone axis orientation) as is the case here, one must be cautious when attempting quantitative EELS and EDX measurements, as these experiments can be convoluted by elastic and thermal diffuse scattering of the incident electrons. 39, 40 However, in the case of the present fine structure analysis, we are simply looking at clear trends in the spectra, which appear and disappear rapidly, generally within a single unit cell, as shown in Figure 4(a);…”

Inelastic Scattering in Electron Backscatter Diffraction and Electron Channeling Contrast Imaging

“…In the incoherent limit (i.e., large collection solid angle), the TDS inelastic scattered intensity is proportional to (Lugg et al, 2014)…”

“…In the incoherent limit (i.e., large collection solid angle), the TDS inelastic scattered intensity is proportional to (Lugg et al, 2014)where V ( r ) is the interaction potential and Ψ n ( r ) is the electron wavefunction with the specimen in the n th-phonon configuration. Equation (5) is integrated over the entire analytical volume.…”

Probing core-electron orbitals by scanning transmission electron microscopy and measuring the delocalization of core-level excitations

“…Core-level orbitals can be determined by deconvolving channeled STEM probes from source-removed EDX maps, a notion that has also been discussed by others [16,18]. The EDX intensity for a given probe position can be evaluated as the convolution of depth-integrated channeling intensity for that probe position with the orbital excitation potential.…”