Dynamical van der Waals atom -surface interaction

TL;DR

This paper derives a new nonrelativistic formula for the dynamical van der Waals atom-surface interaction energy, revealing nonlinear velocity and distance dependence, especially near surfaces and at moderate velocities.

Contribution

It introduces a more general expression for dynamical van der Waals interactions that extends beyond the classical slow-velocity approximation.

Findings

Dynamical van der Waals potential is lower near surfaces at moderate velocities.

Interaction energy shows strong nonlinear dependence on velocity and distance.

Potential approaches static values with increasing distance or decreasing velocity.

Abstract

We obtained new nonrelativistic expression for the dynamical van der Waals atom -surface interaction energy of very convenient form for different applications. It is shown that classical result (Ferrell and Ritchie, 1980) holds only for a very slowly moving atom. In general case, the van der Waals atom -surface interaction energy manifests strong nonlinear dependence on velocity and distance. In close vicinity of metal and dielectric surfaces and velocities from 1 to 10 Bohr units the dynamical van der Waals potential proves to be significantly lower that in static case and goes to the static values with increasing distance and (or) decreasing velocity.