Field strength scaling in quasi-phase-matching of high-order harmonic generation by low-intensity assisting fields

TL;DR

This paper numerically investigates how low-intensity assisting fields can enhance high-order harmonic generation through quasi-phase-matching, analyzing the dependence on various parameters to optimize efficiency.

Contribution

It provides a detailed numerical analysis of field strength scaling in quasi-phase-matching for high-order harmonic generation using assisting fields.

Findings

Assisting field strength depends on wavelength and intensity of the driving field.

Optimal assisting field spatial profile can improve phase-matching.

The study offers guidelines for maximizing harmonic generation efficiency.

Abstract

High-order harmonic generation in gas targets is a widespread scheme used to produce extreme ultraviolet radiation, however, it has a limited microscopic efficiency. Macroscopic enhancement of the produced radiation relies on phase-matching, often only achievable in quasi-phase-matching arrangements. In the present work we numerically study quasi-phase-matching induced by low-intensity assisting fields. We investigate the required assisting field strength dependence on the wavelength and intensity of the driving field, harmonic order, trajectory class and period of the assisting field. We comment on the optimal spatial beam profile of the assisting field.