Double-slit experiment in momentum space

TL;DR

This paper proposes a novel double-slit experiment in momentum space using vortex electrons, enabling interference observation and measurement of the Coulomb phase in charged particle scattering.

Contribution

It introduces a new experimental setup in momentum space with vortex electrons, allowing direct access to the Coulomb phase, which is difficult to measure with traditional methods.

Findings

Interference fringes can be observed in the angular distribution of vortex electron scattering.

The experiment is feasible with current technology.

It provides a new way to measure the Coulomb phase in charged particle interactions.

Abstract

Young's classic double-slit experiment demonstrates the reality of interference when waves and particles travel simultaneously along two different spatial paths. Here, we propose a double-slit experiment in momentum space, realized in the free-space elastic scattering of vortex electrons. We show that this process proceeds along two paths in momentum space, which are well localized and well separated from each other. For such vortex beams, the (plane-wave) amplitudes along the two paths acquire adjustable phase shifts and produce interference fringes in the final angular distribution. We argue that this experiment can be realized with the present day technology. We show that it gives experimental access to the Coulomb phase, a quantity which plays an important role in all charged particle scattering but which usual scattering experiments are insensitive to.