Scientists demonstrated switching between topological and magnetic ground states by controlling the concentration of magnetic defects in a crystal. Controlling electronic topology in magnetic materials demonstrated will provide new opportunities in quantum information and sensing applications.
The combined experimental and theoretical study was enabled by the growth of large single crystals of MnSb2Te4 with controlled amounts of Mn/Sb site mixing. Magnetic susceptibility and neutron diffraction measurements indicate that an increase of the site mixing between the neighboring Mn and Sb sites changes the magnetic state from antiferromagnetic to ferromagnetic, in agreement with the predictions of theory. Theory also indicates that higher defect concentrations are detrimental to the electronic topology. The defect concentration and distribution was accurately measured using neutron diffraction and atomic-scale microscopy probes. This research highlights the critical role that crystalline defects play in the evolution of exotic quantum states of matter.
DOI: 10.1103/PhysRevX.11.021033.
