Attochirp-free High-order Harmonic Generation

TL;DR

This paper introduces a novel method for generating bandwidth-limited attosecond pulses in high-order harmonic generation by shaping laser pulses and using xuv or x-ray ionization, eliminating the need for chirp compensation filters.

Contribution

It presents a new approach to engineer the phase of high-order harmonic generation, enabling direct production of ultrashort pulses without additional filtering.

Findings

Bandwidth-limited 8 as pulses achieved from Li$^{2+}$ gas.

Method extends to z-scaling for broader applications.

Avoids use of filters for chirp compensation.

Abstract

A method is proposed for arbitrarily engineering the high-order harmonic generation phase achieved by shaping a laser pulse and employing xuv light or x rays for ionization. This renders the production of bandwidth-limited attosecond pulses possible while avoiding the use of filters for chirp compensation. By adding the first 8 Fourier components to a sinusoidal field of $10^{16}$W/cm$^2$, the bandwidth-limited emission of 8 as is shown to be possible from a Li$^{2+}$ gas. The scheme is extendable to the zs-scale.