Bias-tunable two-dimensional magnetic and topological materials

TL;DR

This paper introduces a new class of 2D materials based on endohedral fullerenes that exhibit multiple functional properties like ferroelectricity, magnetism, and topological effects, with potential applications in next-generation electronics.

Contribution

The authors design and analyze a series of 2D fullerene-based materials that combine multiple functionalities and propose a novel topological field-effect transistor design.

Findings

Materials exhibit ferroelectricity with large electric dipole moments

Presence of multiple magnetic phases with high Curie temperatures

Observation of quantum spin Hall and quantum anomalous Hall effects

Abstract

Searching for novel two-dimensional (2D) materials is crucial for the development of the next generation technologies such as electronics, optoelectronics, electrochemistry and biomedicine. In this work, we designed a series of 2D materials based on endohedral fullerenes, and revealed that many of them integrate different functions in a single system, such as ferroelectricity with large electric dipole moments, multiple magnetic phases with both strong magnetic anisotropy and high Curie temperature, quantum spin Hall effect or quantum anomalous Hall effect with robust topologically protected edge states. We further proposed a new style topological field-effect transistor. These findings provide a strategy of using fullerenes as building blocks for the synthesis of novel 2D materials which can be easily controlled with a local electric field.