Active absorption of electromagnetic pulses in a cavity

TL;DR

This paper demonstrates that electromagnetic pulses can be fully absorbed into a tiny region within a cavity through precise control of currents, with explicit examples and experimental validation in microwave cavities.

Contribution

It introduces a method for complete electromagnetic pulse absorption in a cavity by controlling currents, supported by theoretical examples and experimental evidence.

Findings

Complete absorption of electromagnetic pulses into a small region is possible.

Explicit cavity designs enable this absorption effect.

Experimental demonstration confirms the theoretical predictions.

Abstract

We show that a pulse of electromagnetic radiation launched into a cavity can be completely absorbed into an infinitesimal region of space, provided one has a high degree of control over the current flowing through this region. We work out explicit examples of this effect in a cubic cavity and a cylindrical one, and experimentally demonstrate the effect in the microwave regime.