Two concurrent exponential decays in a vacuum capacitor-resistor circuit: effect of surface charge

TL;DR

This paper investigates the dual exponential decay phenomena in vacuum capacitor-resistor circuits, highlighting the influence of surface charge and providing experimental support for a phenomenological model that applies broadly to various capacitors.

Contribution

It introduces a simple phenomenological model explaining dual exponential decays in vacuum capacitors, emphasizing the role of surface charge, supported by experimental measurements.

Findings

Two exponential decay processes observed in vacuum circuits.

Surface charge significantly affects relaxation behavior.

Model applies to different capacitor types, including polypropylene.

Abstract

The relaxation in a vacuum capacitor-resistor circuit is comprised of two exponential decays, one caused by surface charge and the other by the decay of energy stored between the capacitor plates. A simple phenomenological model of this relaxation is shown to be supported by measurements even though Maxwell's equations are difficult to apply in this case. Similar behavior is also observed for polypropylene capacitors, indicating that this surface charge effect is applicable to all capacitors and potentially other circuit components.