# $\textit{Ab Initio}$ Mismatched Interface Theory of Graphene on $\alpha$-RuCl$_3$: Doping and Magnetism

## TL;DR

This paper introduces a new ab initio method called mismatched interface theory (MINT) for studying heterobilayers with no periodicity, applied to graphene on $ extit{α}$-RuCl$_3$, predicting doping and magnetic shifts.

## Contribution

The paper develops MINT, a novel ab initio framework for mismatched heterobilayers, and applies it to predict doping and magnetic properties in graphene/$ extit{α}$-RuCl$_3$.

## Key findings

- Predicts 4.77% doping from graphene to $ extit{α}$-RuCl$_3$
- Shows magnetic interactions shift towards the Kitaev point
- Demonstrates MINT's potential for guiding material design

## Abstract

Recent developments in twisted and lattice-mismatched bilayers have revealed a rich phase space of van der Waals systems and generated excitement. Among these systems are heterobilayers which can offer new opportunities to control van der Waals systems with strong in plane correlations such as spin-orbit-assisted Mott insulator $\alpha$-RuCl$_3$. Nevertheless, a theoretical $\textit{ab initio}$ framework for mismatched heterobilayers without even approximate periodicity is sorely lacking. We propose a general strategy for calculating electronic properties of such systems, mismatched interface theory (MINT), and apply it to the graphene/$\alpha$-RuCl$_{3}$ (GR/$\alpha$-RuCl$_{3}$) heterostructure. Using MINT, we predict uniform doping of 4.77$\%$ from graphene to $\alpha$-RuCl$_3$ and magnetic interactions in $\alpha$-RuCl$_3$ to shift the system toward the Kitaev point. Hence we demonstrate that MINT can guide targeted materialization of desired model systems and discuss recent experiments on GR/$\alpha$-RuCl$_{3}$ heterostructures.