English

Wave-packet numerical investigation of thermal diffuse scattering: A time-dependent quantum approach to the Debye method

Computational Physics 2018-01-22 v1 Materials Science Quantum Physics

Abstract

The effects of thermal diffuse scattering on the transmission and eventual diffraction of highly accelerated electrons are investigated with a method that incorporates the frozen phonon approximation to the exact numerical solution of the time-dependent Schr\"odinger equation. Unlike other methods in the related literature, in this approach the attenuation of diffraction features arises in a natural way by averaging over a number of wave-packet realizations, thus avoiding any additional experimentally obtained Debye-Waller factors or artificial modulations. Without loss of generality, the method has been applied to analyze the transmission of an electron beam through a thin Al film in two dimensions, making use of Einstein's model to determine the phonon configuration for each realization at a given temperature. It is shown that, as temperature and hence atomic vibration amplitudes increase, incoherence among different electron wave-function realizations gradually increases, blurring the well-defined diffraction features characterizing the zero-temperature intensity.

Keywords

Cite

@article{arxiv.1801.05869,
  title  = {Wave-packet numerical investigation of thermal diffuse scattering: A time-dependent quantum approach to the Debye method},
  author = {S. Rudinsky and A. S. Sanz and R. Gauvin},
  journal= {arXiv preprint arXiv:1801.05869},
  year   = {2018}
}