Sensitivity-Enhanced Electron-Holographic Interferometry and Thickness-Measurement Applications at Atomic Scale

Abstract

An electron phase shift down to an order of $\frac{\lambda }{100}$ ($\lambda$ is wavelength) was detected for the first time. This was realized by applying longitudinally reversed shearing interferometry in the optical reconstruction stage of electron holography. Thickness changes due to monatomic steps in Mo${\mathrm{S}}_2$ films were clearly observed in phase-amplified interference micrographs.