The highly intertwined magnetic and electronic properties of magnetic topological materials (MTMs) make MTMs valuable for electrical control of magnetism and vice versa, e.g. in spintronic devices, as well as for quantum electronics, as an ingredient in proposed topological quantum computation devices. Mn(Bi, Sb)2Te4, a family of MTMs with highly tunable properties, is an ideal playground for studying the interplay of band topology with magnetism. While previous work has focused on uniform ordered phases, here we ask: How can we control the electronic properties of Mn(Bi, Sb)2Te4 using the mesoscale structure of magnetism?
By combining domain manipulation and imaging in a cryogenic magnetic force microscope (MFM) with in-situ electrical transport measurements, we measure the impact of the local magnetic order on electrical transport in a device of ferrimagnetic MnSb2Te4 (FM-MST). We directly measure the impact of local magnetization on the electrical response, and the linear scaling of the anomalous Hall response with magnetic domain volume.
This work demonstrates that M(Bi,Sb)2Te4 can be used to introduce programmable magnetic landscapes into 2D materials heterostructures. Furthermore, our technique to control domain geometry through explicit manipulation accesses both “boundary” and “bulk” responses to magnetic domains, a tool for studying the interplay between magnetism and electrical response in MTMs more broadly.
