High-order harmonics and supercontinua formed by a weak optical pump in the presence of an extreme terahertz field

authored by

I. Babushkin, A. Demircan, U. Morgner, A. Savel'Ev

Abstract

We show that in the presence of an extreme terahertz (THz) field an additional weak field in the optical frequency range can modulate ionization probability and thereby generate high-order harmonics. The extreme THz pump suppresses recollisions, thereby also fully suppressing the recollision-based harmonics. Nevertheless, high-order harmonics are effectively generated via an alternative mechanism, the so-called Brunel mechanism, based on ionization and subsequent acceleration in the driving field (but not on reabsorption). Using ab initio simulations for the hydrogen atom and short few-cycle optical driver, we show the appearance of a coherent carrier-envelope-phase-insensitive supercontinuum formed by such harmonics, compressible into an isolated pulse with 100-attosecond-scale duration.

Organisation(s)

Institute of Quantum Optics
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines

External Organisation(s)

Lomonosov Moscow State University

Type

Article

Journal

Physical Review A

Volume

106

ISSN

2469-9926

Publication date

28.07.2022

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Atomic and Molecular Physics, and Optics

Electronic version(s)

https://doi.org/10.48550/arXiv.2105.04627 (Access: Open)
https://doi.org/10.1103/PhysRevA.106.013115 (Access: Closed)