# Transition between canted antiferromagnetic and spin-polarized ferromagnetic quantum Hall states in graphene on a ferrimagnetic insulator

## TL;DR

This study demonstrates how magnetic proximity effects in graphene on a ferrimagnetic insulator enable tuning between antiferromagnetic and ferromagnetic quantum Hall states with relatively low magnetic fields, advancing control of 2D magnetic states.

## Contribution

It reveals the influence of magnetic proximity coupling on the quantum Hall states in graphene, showing a tunable transition facilitated by an induced exchange field.

## Key findings

- Induced magnetic exchange field in graphene lowers the transition field.
- Transition between magnetic states can be controlled with magnetic fields > 6 T.
- Proximity coupling enhances tunability of magnetic states in 2D materials.

## Abstract

In the quantum Hall regime of graphene, antiferromagnetic and spin-polarized ferromagnetic states at the zeroth Landau level compete, leading to a canted antiferromagnetic state depending on the direction and magnitude of an applied magnetic field. Here, we investigate this transition at 2.7 K in graphene Hall bars that are proximity coupled to the ferrimagnetic insulator Y$_{3}$Fe$_{5}$O$_{12}$. From nonlocal transport measurements, we demonstrate an induced magnetic exchange field in graphene, which lowers the magnetic field required to modulate the magnetic state in graphene. These results show that a magnetic proximity effect in graphene is an important ingredient for the development of two-dimensional materials in which it is desirable for ordered states of matter to be tunable with relatively small applied magnetic fields (> 6 T).

---
Source: https://tomesphere.com/paper/1905.06866