Electric field driven spin textures in heavy fermion van der Waals magnets

TL;DR

This paper investigates how electric fields can control spin textures in heavy fermion van der Waals magnets, revealing tunable magnetic phases and the emergence of a vortex phase through an effective spin model.

Contribution

It introduces a model showing electric field tuning of magnetic interactions in CeSiI monolayers, enabling control over magnetic orders and stabilization of a vortex phase.

Findings

Electric field can tune Kondo coupling in CeSiI monolayers.

Different magnetic orders can coexist due to electric field tuning.

A vortex magnetic phase can be stabilized with an external electric field.

Abstract

The recently discovered van der Waals material CeSiI exhibits both heavy fermion behavior and spiral order with strong magnetic anisotropy which makes it a potential host for topological spin textures such as skyrmions through electrical gating. A monolayer of CeSiI consists of two layers of Ce atoms on triangular lattices that sandwich a silicene layer. Motivated by the experiments, we explore magnetic phase diagram in van der Waals heavy fermion materials as a function of anisotropy and applied magnetic field using an effective spin model. We demonstrate that application of an external electric field can tune the Kondo coupling on each Ce layer differently, in turn allowing for controlling the intra- and interlayer magnetic couplings. Our analysis indicates that this fine-tuning leads to the coexistence of different magnetic orders in a single monolayer. In particular, we show that a novel vortex phase can be stabilized only in the presence of an external electric field. Our results highlight the unique advantages and the tunability of van der Waals heavy fermion materials for manipulation of chiral magnetic phases.