Casimir rack and pinion: Mechanical rectification of periodic multi-harmonic signals

TL;DR

This paper investigates a noncontact Casimir rack and pinion system that acts as a mechanical rectifier, converting periodic multi-harmonic signals into unidirectional rotation and lifting loads, with thermal noise potentially aiding its function.

Contribution

It demonstrates that a Casimir-based rack and pinion can serve as a mechanical rectifier under realistic conditions, including room temperature and multi-harmonic inputs.

Findings

The device achieves a nonzero average rotation velocity.

Thermal noise can enhance the rectification process.

The system can lift external loads in a broad parameter range.

Abstract

We study noncontact rack and pinion composed of a corrugated plate and a corrugated cylinder intermeshed via the lateral Casimir force. We assume that the rack position versus time is a periodic multi-harmonic signal. We show that in a large domain of parameter space and at room temperature, the device acts as a mechanical rectifier: The pinion rotates with a nonzero average velocity and lifts up an external load. The thermal noise may even facilitate the device operation.