# Controlling Magnetism in the 2D van der Waals Antiferromagnet CrPS4 via Ion Intercalation

## TL;DR

This paper shows how inserting ions into a 2D magnetic material can change its magnetic properties and improve its performance for electronic applications.

## Contribution

The study demonstrates that ion intercalation can switch magnetic states and significantly enhance ordering temperatures in CrPS4.

## Key findings

- Li+ intercalation turns CrPS4 from a semiconductor to a metal and changes its magnetic state from antiferromagnetic to ferromagnetic.
- TBA+ intercalation increases the van der Waals gap and stabilizes in-plane ferromagnetism with a Curie temperature above 100 K.
- Intercalation enhances magnon transport properties and makes them more isotropic.

## Abstract

Two-dimensional (2D) van der Waals (vdW) magnetic materials
are
platforms in which inserting chemical species into their interlayer
gaps offers a powerful route to engineer magnetism. Here, we focus
on the A-type antiferromagnetic semiconductor CrPS4 (T
N = 38 K) and investigate its electronic and
magnetic properties upon intercalation of lithium (Li+)
and organic tetrabutylammonium (TBA+) ions using first-principles
calculations. Li+ incorporation induces a semiconductor-to-metal
transition in CrPS4 and triggers a switching from an out-of-plane
antiferromagnetism state to an in-plane ferromagnetic state. This
is accompanied by an increase of the ordering temperature, reaching
a 5-fold enhancement for Li0.5CrPS4. TBA+ intercalation expands the vdW gap, decoupling CrPS4 layers and stabilizing in-plane ferromagnetism with T
C > 100 K. Furthermore, it enhances magnon group velocities
and yields more isotropic magnon transport. This work highlights intercalation
as a powerful approach for tailoring magnetism, paving the way for
tunable 2D-layered magnetic materials for spintronic and magnonic
applications.