Impact of B-doping on topological Hall resistivity in (111)- and (110)-oriented Mn₄N single layers with the non-collinear spin structure

Controllability of the topological Hall resistivity (ρ_xy^THE) via the doping effect of light elements was investigated for the sputter-deposited (111)-oriented Mn₄N single layer. The component of ρ_xy^THE relative to the anomalous Hall resistivity (ρ_xy^AHE) for host Mn₄N was found to increase with decreasing temperature. Boron (B), one of the 2p light elements acting as an interstitial impurity, was doped to the (111)-oriented Mn₄N single layer. The microstrain, grain diameter, and surface roughness were found to decrease, resulting in the reduction of ρ_xy^THE for all temperatures without a change in the antiperovskite bone structure of Mn₄N. These results show a dilution effect in the spin frustration state with topological spin texture by B-doping. The effect of B on ρ_xy^THE for a different orientation of (110) was similar to that of (111), while the enhancement of ρ_xy^THE was observed by a higher amount of B. B-doping could, thus, be a promising approach to realize tailor-made spintronic devices based on the topological spin state owing to its material versatility.