Emergence of a Luttinger Liquid Phase in an Array of Chiral Molecules

TL;DR

This paper proposes using arrays of chiral molecules to simulate quantum magnetism, demonstrating that molecular stereochemistry naturally induces Dzyaloshinskii-Moriya interactions, leading to a chiral Luttinger liquid phase.

Contribution

It introduces a platform of trapped asymmetric top molecules for simulating chiral quantum magnetism, deriving an effective Hamiltonian, and showing how molecular stereochemistry induces DMI.

Findings

DMI emerges naturally from molecular stereochemistry.

A phase diagram identifies optimal parameters for observing the chiral Luttinger liquid.

The system exhibits a robust gapless spin-spiral texture.

Abstract

We propose a robust platform for simulating chiral quantum magnetism using linear arrays of trapped asymmetric top molecules, specifically 1,2-propanediol ($\mathrm{C_{3}H_{8}O_{2}}$). By mapping the Stark-dressed rotational states onto an effective spin-$1/2$ subspace, we rigorously derive a generalized $XXZ$ Heisenberg Hamiltonian governing the underlying many-body dynamics. Unlike standard solid-state models where the topological Dzyaloshinskii-Moriya Interaction (DMI) is introduced phenomenologically, we demonstrate that DMI emerges \textit{ab initio} from the molecular stereochemistry. Specifically, the interference between the transition dipole moments of heterochiral enantiomer pairs (L-R), which breaks inversion symmetry, generates a tunable DMI that stabilizes a Chiral Luttinger Liquid phase. Through a comprehensive phase-diagram analysis, we identify an optimal experimental regime characterized by intermolecular separations of \( r \approx 1.5~\mathrm{nm} \) and intermediate electric-field strengths \( d\varepsilon/B \approx 2.5 \). In this window, the system is protected from trivial field-polarized phases and exhibits a robust gapless spin-spiral texture. Our results establish 1,2-propanediol arrays as a versatile quantum simulator, providing a direct microscopic link between molecular chirality and topological many-body phases.