Fig. 2: Separating the influence of metallic ferromagnetic domain walls.

a, b Schematics of the measurement procedure using the two-rotator setup. Every galvanomagnetic Cd₂Os₂O₇ sample (gray plate) is field-cooled in two stages: a field H is aligned parallel to the sample surface at room temperature before cooling down through T_N, and b the sample is rotated below T_N to have a field perpendicular to its surface for galvanomagnetic measurements. The in-plane magnetizing direction is defined by angle ϕ at 24 discrete positions, set outside the cryostat at room temperature. c Typical raw data of Hall resistances R(H) between two reciprocal channels, measured for sample COO-2 at a specified temperature and magnetization angle ϕ. The difference in slopes indicates the influence of asymmetric linear magnetoresistance from ferromagnetic domain walls²¹. (inset) vdP configuration for the two reciprocal Hall channels. d–f ϕ-dependence of Hall resistivity slopes R_H in two reciprocal channels (red and blue) and their average (fresh green), in addition to the resistivity ρ (green) and vdP ratio (orange), measured in sample COO-2 at three temperatures 195, 30, and 1.8 K. (Methods) (g) Hall resistivity slopes R_H from two reciprocal channels (red and blue) are plotted alongside their average (fresh green) for two different single-crystal Cd₂Os₂O₇ samples COO-1 and COO-2. Although the resistance slopes of an individual Hall channel are very different for each sample, with occasional crossings at various temperatures, the averages are similar in shape between the two samples and determine the bulk Hall coefficient R_H(T). This irregular behavior of resistance slopes of individual Hall channels highlights potential experimental deficiencies in previous Hall measurements. All statistical uncertainties are smaller than the symbols.