Fig. 4: Analysis of the current distribution in the CNP regime.

a Difference image of the two current flux images with opposite magnetization and the same bias direction (Fig. 2c, d). b Current density image reconstructed from the difference current flux image in (e). The subtraction removes the flux contribution from the non-chiral bulk current (\({I}_{{{\rm{n}}}}\)) while keeping one of the chiral edge currents (\({I}_{{{\rm{l}}}}^{+}\)) and reversing the \({I}_{{{\rm{u}}}}^{-}\) to \({I}_{{{\rm{u}}}}^{+}\) so that the difference image shows a circulation around the 7-SL clockwise. c and d The sum current flux of Fig. 2c, d and its current density reconstruction, respectively. The sum image doubles the non-chiral contribution while adding the chiral edge currents with opposite chirality: 2\({I}_{{{\rm{n}}}}+{I}_{{{\rm{l}}}}^{+}+{I}_{{{\rm{u}}}}^{-}\). Thus, the direction of flow in the sum image is the same for both bulk and two edge currents. e Line cuts from the difference (orange) and sum (green) current flux images across the upper and lower edges shown by the dashed lines in (a and c), in comparison with that from the current flux obtained with a pure AC current (red) at the same ___location. The purple curve is a cut from the current flux image at \({V}_{{{\rm{g}}}}=\) 0 V (Fig. 3a), representing the current carried mostly by the bulk. Note that the sum current flux (green) is two times larger than the pure AC current flux (red) with a similar profile, in quantitative agreement with our analysis of the two measurement schemes (Fig. 1g, k). f Line cuts from the current density J images in (b and d) at the same position, representing the chiral (orange) and the sum (green), respectively. A cut from J obtained with pure AC drive (red) is shown in comparison with the sum (green). The non-chiral current density (black) is obtained by subtracting the chiral current density from the sum and then dividing by 2. The bulk current (purple) is obtained from the line cut of J reconstructed from the current flux image at 0 V (Fig. 3a).