Tapering Enhanced Stimulated Superradiant Amplification

TL;DR

This paper introduces a novel mechanism using tapered undulators for stimulated superradiant emission, enabling efficient conversion of electron beam energy into high-power, tunable, narrow-band radiation with potential for very high average power sources.

Contribution

It presents a new method for optimizing undulator tapering to enhance stimulated superradiant emission, improving power extraction efficiency.

Findings

Potential to extract ~50% of electron beam power

Enables coherent narrow-band tunable radiation

Pathway to very high average power sources

Abstract

High conversion efficiency between electrical and optical power is highly desirable both for high peak and high average power radiation sources. In this paper, we discuss a new mechanism based on stimulated superradiant emission in a strongly tapered undulator whereby an optimal undulator tapering is calculated by dynamically matching the resonant energy variation to the ponderomotive decelerating gradient. The method has the potential to allow the extraction of a large fraction (~50%) of power from a relativistic electron beam and convert it into coherent narrow-band tunable radiation, and shows a clear path to very high average power radiation sources.