Tangle of Spin Double Helices in the Honeycomb Kitaev-$\Gamma$ Model

TL;DR

This paper explores the complex spin structures in the honeycomb Kitaev-$Gamma$ model, revealing a tangle of double helices with distinct anisotropy and chirality, through classical and quantum simulations.

Contribution

It uncovers the detailed spin double helix structures and their properties in the Kitaev-$Gamma$ model, combining classical and quantum approaches for the first time.

Findings

Identification of a tangle of highly structured spin double helices.

Discovery of 18 inequivalent helical axes and anisotropic periodicity.

Quantum simulations reveal signatures of these structures in the ground state.

Abstract

We investigate the ground-state nature of the honeycomb Kitaev-$\Gamma$ model in the material-relevant parameter regime through a combination of classical and quantum simulations. The classical model is imprinted with a tangle of highly structured spin double helices. This helix tangle exhibits $18$ inequivalent helical axes and features a spontaneous periodicity anisotropy and a ${\rm sgn}(\Gamma)$-determined chirality pattern. Infinite PEPS simulations with clusters up to $36$ sites identify hallmarks of this many-body order in the quantum spin-$1/2$ model. Our findings provide a fresh perspective of the Kitaev-$\Gamma$ model and enrich the physics of Kitaev magnetism.