Analysis of electromagnetic forces and causality in electron microscopy

Abstract

The non-physical effects on the transverse momentum transfer from fast electrons to gold nanoparticles associated to the use of non-causal dielectric functions are studied. A direct test of the causality based on the surface Kramers-Kronig relations is presented. This test is applied to the different dielectric function used to describe gold nanostructures in electron microscopy.

Keywords: Electron microscopy; Kramers–Kronig; Metals; Optical properties.