Inducing enantiosensitive permanent multipoles in isotropic samples with two-color fields

TL;DR

This paper demonstrates that two-color laser fields can induce enantiosensitive permanent multipoles in isotropic chiral molecules, with control over their orientation and type (dipoles or quadrupoles) via phase manipulation.

Contribution

It introduces a novel method to generate and control enantiosensitive permanent multipoles in isotropic samples using two-color fields, including the first demonstration of enantiosensitive permanent quadrupoles.

Findings

Two-color fields induce enantiosensitive permanent dipoles in chiral molecules.

Relative phase controls the orientation and type of induced multipoles.

Quadrupoles can be enantiosensitive even when dipoles are not.

Abstract

We find that two-color fields can induce field-free permanent dipoles in initially isotropic samples of chiral molecules via resonant electronic excitation in a one-$3\omega$-photon vs. three-$\omega$-photons scheme. These permanent dipoles are enantiosensitive and can be controlled via the relative phase between the two colors. When the two colors are linearly polarized perpendicular to each other, the interference between the two pathways induces excitation sensitive to the molecular handedness and orientation, leading to uniaxial orientation of the excited molecules and to an enantio-sensitive permanent dipole perpendicular to the polarization plane. We also find that although a corresponding one-$2\omega$-photon vs. two-$\omega$-photons scheme cannot produce enantiosensitive permanent dipoles, it can produce enantiosensitive permanent quadrupoles that are also controllable through the two-color relative phase.