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 (ρxyTHE) via the doping effect of light elements was investigated for the sputter-deposited (111)-oriented Mn4N single layer. The component of ρxyTHE relative to the anomalous Hall resistivity (ρxyAHE) 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 ρxyTHE 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 ρxyTHE for a different orientation of (110) was similar to that of (111), while the enhancement of ρxyTHE 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.