Control of attosecond light polarization in two-color bi-circular fields

TL;DR

This paper presents a comprehensive analytical model, validated through experiments and simulations, that explains and controls the polarization of high harmonics generated by two-color counter-rotating laser fields, enabling tailored attosecond pulse polarization.

Contribution

It introduces a new analytical framework for understanding and manipulating the polarization properties of high harmonic generation in two-color bi-circular fields.

Findings

Identified three key propensity rules governing harmonic emission.

Confirmed the rules through numerical simulations and experiments.

Demonstrated control of attosecond pulse polarization via laser parameters.

Abstract

We develop theoretically and confirm both numerically and experimentally a comprehensive analytical model which describes the propensity rules in the emission of circularly polarized high harmonics by systems driven by two-color counter-rotating fields, a fundamental and its second harmonic. We identify and confirm the three propensity rules responsible for the contrast between the 3N+1 and 3N+2 harmonic lines in the HHG spectra of noble gas atoms. We demonstrate how these rules depend on the laser parameters and how they can be used in the experiment to shape the polarization properties of the emitted attosecond pulses.