An inelastic multislice simulation method incorporating plasmon energy losses

Abstract

Quantitative electron microscopy requires accurate simulation methods that take into account both elastic and inelastic scattering of the high energy electrons within the specimen. Here a method to combine plasmon excitations, the dominant energy loss mechanism in a solid, with conventional frozen phonon, multislice simulations is presented. The Monte Carlo based method estimates the plasmon scattering path length and scattering angle using random numbers and modifies the transmission and propagator functions in the multislice calculation accordingly. Comparison of energy filtered, convergent beam electron diffraction patterns in [110]-Si show good agreement between simulation and experiment. Simulations also show that plasmon excitation decreases the high angle annular dark field signal from atom columns, due to the plasmon scattering angle suppressing electron beam channeling along the atom columns. The effect on resolution and peak-to-background ratio of the atom columns is however small.