# Tunable quantum anomalous Hall effect in fullerene monolayers

## TL;DR

This paper proposes a new molecular design approach using C26 fullerene monolayers to realize tunable quantum anomalous Hall effects, offering a feasible route for experimental realization.

## Contribution

It introduces a 2D honeycomb lattice of C26 fullerenes as a tunable platform for QAH physics with controllable magnetic and strain parameters.

## Key findings

- Exhibits ferromagnetic ground state breaking time-reversal symmetry
- Displays a rich phase diagram with multiple Chern numbers
- Offers a chemically synthesizable route for QAH materials

## Abstract

Nearly four decades after its theoretical prediction, the search for material realizations of quantum anomalous Hall effect (QAHE) remains a highly active field of research. Many materials have been predicted to exhibit quantum anomalous Hall (QAH) physics under feasible conditions but the experimental verification remains widely elusive. In this work, we propose an alternative approach towards QAH materials design by engineering customized molecular building blocks. We demonstrate this ansatz for a two-dimensional (2D) honeycomb lattice of C26 fullerenes, which exhibits a ferromagnetic ground state and thus breaks time-reversal symmetry. The molecular system is found to be highly tunable with respect to its magnetic degrees of freedom and applied strain, giving rise to a rich phase diagram with Chern numbers C= +/-2, +/-1, 0. Our proposal offers a versatile platform to realize tunable QAH physics under accessible conditions and provides an experimentally feasible approach for chemical synthesis of molecular networks with QAHE.