Stimulated excitation of an optical cavity by a multi-bunch electron beam via coherent diffraction radiation process

TL;DR

This paper demonstrates stimulated excitation of an optical cavity in the terahertz range using a high-repetition-rate, low-emittance electron beam passing through the cavity without destruction, showing wide-band stimulated emission.

Contribution

It presents a novel experimental setup for stimulating an optical cavity with a multi-bunch electron beam via coherent diffraction radiation at terahertz frequencies.

Findings

Observation of sharp resonance structures indicating stimulated emission.

Successful excitation of the cavity without damaging the electron beam.

Evidence of wide-band stimulated emission via coherent diffraction radiation.

Abstract

With a low emittance and short-bunch electron beam at a high repetition rate realized by a superconducting linac, stimulated excitation of an optical cavity at the terahertz spectrum range has been shown. The electron beam passed through small holes in the cavity mirrors without being destroyed. A sharp resonance structure which indicated wide-band stimulated emission via coherent diffraction radiation was observed while scanning the round-trip length of the cavity.