Magnetic topological transistor exploiting layer-selective transport

Abstract

We propose a magnetic topological transistor based on ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$, in which the ``on'' state (quantized conductance) and the ``off'' state (zero conductance) can be easily switched by changing the relative direction of two adjacent electric fields (parallel vs antiparallel) applied within a two-terminal junction. We explain that the proposed magnetic topological transistor relies on a novel mechanism due to the interplay of topology, magnetism, and layer degrees of freedom in ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$. Its performance depends substantially on film thickness and type of magnetic order. We show that ``on'' and ``off'' states of the transistor are robust against disorder due to the topological nature of the surface states. Our work opens an avenue for applications of layer-selective transport based on the topological van der Waals antiferromagnet ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$.