Impact of Rotation on the Retarded Interaction between a Permanent Dipole Particle and a Polarizable Surface

TL;DR

This paper investigates how rotation affects the interaction energy and torque of a small dipole particle near a surface, considering retardation effects and different orientations, revealing conditions for stable rotation or repulsion.

Contribution

It provides a detailed analysis of the rotational effects on dipole-surface interaction energy and torque, including retardation, for various orientations of the dipole.

Findings

Particle can revolve indefinitely without damping when aligned with rotation axis.

Inclined dipole axes can lead to particle repulsion and increased spin.

Retardation effects significantly influence the interaction dynamics.

Abstract

We have calculated components of torque and the interaction energy of small rotating particle with a permanent dipole moment in the case where the rotation axis is perpendicular to the surface and the dipole axis is inclined to it. The retardation effects were taken into account. An important property of this system is its quasistationarity. When the dipole axis coincides with the rotation axis, the particle does not experience damping and may revolve for infinitely long time. When the axis of dipole particle is inclined to the surface, the situation is possible where the particle is repelled off the surface and its spin increases.