High spatial resolution diffraction diagnostics for intense terahertz sources

TL;DR

This paper introduces a high-resolution spatial diagnostic method using a millimeter-gap grating to monitor minute variations in intense terahertz beams, enhancing understanding and control of terahertz sources.

Contribution

The paper presents a novel diagnostic technique that improves spatial resolution in terahertz beam analysis by inserting a specialized grating, verified through experimental tuning of the infrared pump beam.

Findings

The method successfully detects tiny beam variations.

The phenomena are explained by tilted pulse front theory and diffraction.

Potential applications in strong-field terahertz technologies.

Abstract

We propose a high resolution spatial diagnostic method via inserting a millimeter-gap grating into the collimated terahertz beam to monitor the minute variation of the terahertz beam in strong-field terahertz sources, which is difficult to be resolved in conventional terahertz imaging systems. To verify the method, we intentionally fabricate tiny variations of the terahertz beam through tuning the iris for the infrared pumping beam before the tilted pulse-front pumping (TPFP) setups. The phenomena can be well explained by the the theory based on tilted pulse front technique and terahertz diffraction. We believe our observation not only help further understand the mechanism of intense terahertz generation, but also may be useful for strong-field terahertz applications.