Giant chiro-optical response in high harmonic generation

TL;DR

This paper demonstrates a giant chiro-optical response in high harmonic generation driven solely by electric-dipole interactions, enabling enhanced detection of molecular chirality through a novel non-collinear setup.

Contribution

It introduces a new method to induce strong chiral signals in HHG using purely electric-dipole interactions, bypassing magnetic effects.

Findings

Giant chiro-optical response achieved with electric-dipole interactions.

Non-collinear configuration maps the response into far-field signals.

Potential for improved chiral molecule detection in ultrafast spectroscopy.

Abstract

High harmonic generation (HHG) records the ultrafast electronic response of matter to light, encoding key properties of the interrogated quantum system, such as chirality. The first implementation of chiral HHG [Cireasa et al. Nat. Phys. 11, 654 (2015)] relied on the weak electronic response of a medium of randomly oriented chiral molecules to the magnetic component of an elliptically polarized wave, yielding relatively weak chiro-optical signals. Here we show that elliptically polarized light can drive a strong chiral response in chiral molecules via purely electric-dipole interactions -- the magnetic component of the wave does not participate at all. This giant chiro-optical response, which remains hidden in standard HHG experiments, can be mapped into the macroscopic far-field signal using a non-collinear configuration, creating new opportunities for bringing the electric-dipole "revolution" to HHG.