Spin-Orbit Driven Topological Phases in Kagome Materials

TL;DR

This paper investigates how spin-orbit coupling influences topological phases in kagome materials, revealing tunable topological states and phase transitions, supported by theoretical modeling and first-principles calculations.

Contribution

It introduces a relativistic model for IAMX kagome materials showing SOC-driven topological phase transitions and validates findings with first-principles calculations.

Findings

SOC induces topological phase transitions in IAMX materials

Surface states evolve continuously with SOC strength

First-principles calculations confirm model predictions

Abstract

Kagome materials have garnered substantial attention owing to their diverse physical phenomena, yet canonical systems such as the AV$_3$Sb$_5$ family exhibit poor $Z_{2}$-type topological properties, spurring an urgent quest for kagome platforms hosting ideal topological states. Recently, Zhou et al. proposed the kagome-type IAMX family, which exhibits distinctive ideal topological states; however, their analysis is primarily restricted to the spinless approximation. In this work, we model relativistic effects in the IAMX family, demonstrating that tuning the spin-orbit coupling (SOC) strength drives topological phase transitions and induces novel topological states, resulting in a rich phase diagram. The configuration of topological surface states evolves continuously as the SOC strength is modulated, consistent with the evolution of the topological phase transition. This suggests a viable route toward designing multi-functional topological devices. First-principles calculations performed on three specific IAMX compounds confirm that SOC governs their topological phases, in complete accord with our model analysis.